Story highlights Mayor of Moore does not expect death toll beyond 24

Ja'Nae Hornsby, 9, is among the children killed at the school, her father says

Authorities revise death toll downward to 24, including nine children

Crews going "board by board" in search for survivors, victims, official says

A search-and-rescue effort to find survivors of a monster tornado that pulverized a vast swath of the suburbs of Oklahoma City shifted Tuesday to one of recovery, officials said.

No new survivors or bodies have been found since the early hours after the tornado carved a trail 17 miles long on Monday afternoon.

"We feel like we have basically gone from rescue and searching to recovery," Glenn Lewis, the mayor of hard-hit Moore, told CNN's Anderson Cooper.

Lewis said he didn't expect the death toll to climb any higher. At least 24 people, including nine children, were killed, according to the state medical examiner's office.

"I think that will stand," Lewis said.

Earlier reports of at least 51 deaths were erroneous, said Amy Elliot, chief administrative officer for the Oklahoma Office of the Chief Medical Examiner. In the chaotic aftermath of the tornado, Elliot said it appeared some of the dead were counted twice.

Photos: Photos: Deadly tornado hits Oklahoma Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A message is left by a homeowner who lost his home in the May 20 tornado on Monday, May 27, in Moore, Oklahoma. View more photos of the aftermath in the region and another gallery of aerial shots of the damage Hide Caption 1 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Left to right, Jaqi Castro, Angelica Morris-Smith and Cetoria Petties walk through a tornado ravaged neighborhood handing out supplies to residents and fellow volunteers on May 27. Hide Caption 2 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Residents gather in the First Baptist Church for the Oklahoma Strong memorial service on Sunday, May 26, to honor victims of the recent deadly tornado in Moore, Oklahoma. Hide Caption 3 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Preschooler Keltin Marazzi, front center, stands on stage with other school children during the memorial service. Hide Caption 4 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Oklahoma Gov. Mary Fallin addresses the audience on May 26. Hide Caption 5 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Tornado victims Christa and Russell Smith hug their children, Evan and Justin Smith, as the service takes place. Hide Caption 6 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Plaza Towers Elementary School teacher Jennifer Doan is comforted by her fiance, Nyle Rogers, on May 26. Hide Caption 7 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – President Barack Obama is greeted as he tours the tornado-ravaged area near Moore, Oklahoma, on Sunday, May 26. Hide Caption 8 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Volunteers bow their heads in reverence on Saturday, May 25, in front of a memorial at the Plaza Towers Elementary School where seven children died during the devastating tornado, in Moore, Oklahoma, on May 20. Hide Caption 9 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Mike Hitch prepares to pull a classic Corvette from under the debris of a home destroyed by Monday's tornado on May 25. Hide Caption 10 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Mike Hitch loads a salvaged Corvette pulled from the rubble onto a tow truck in Moore on May 25. Hide Caption 11 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Eunice Lassiter sits in the driveway of a friend's tornado-damaged home on May 25 in Moore. Hide Caption 12 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A volunteer signs a cross on May 25 at a makeshift memorial outside of the destroyed Plaza Towers Elementary School where seven children were killed in Monday's tornado in Moore. Hide Caption 13 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Volunteers unload donated items for tornado victims at the Yellow Rose Theater on May 25 in Moore. Hide Caption 14 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Volunteer Brittany Pendergraft organizes donated tornado relief items inside the Yellow Rose Theater on May 25 in Moore. Hide Caption 15 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Eddie Jones of the Christian Life Center in Rolla, Missouri, cooks for residents and volunteers helping with tornado relief on May 25 in Moore. Hide Caption 16 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Carol Kawaykla holds a picture of her mother she found in the rubble of her tornado-devastated home in Moore, Oklahoma, on May 24. Hide Caption 17 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – The sun sets over debris from houses littering the ground in Moore, Oklahoma, on Thursday, May 23, three days after the town was damaged by a tornado. Hide Caption 18 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Debris is scattered across a driveway on May 23. Severe thunderstorms barreled through this Oklahoma City suburb at dawn Thursday, complicating cleanup efforts. Hide Caption 19 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Lightning strikes during a thunderstorm as people search for items that can be saved from their devastated home on May 23. Hide Caption 20 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A devastated neighborhood is seen on May 23 in Moore. Hide Caption 21 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A woman searches for belongings at a home on May 22 in Moore. Hide Caption 22 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Michael Pritz swings a golf club while taking a break from helping his friend to salvage belongings on May 22. Hide Caption 23 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Debris litters what remains of a classroom at Plaza Towers Elementary School on May 22. Seven children died at the school in Monday's tornado. Hide Caption 24 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A makeshift shelter stands next to a home destroyed by the tornado on May 22. Hide Caption 25 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Casey Angle walks on the bunk bed she shared with her sister Sydney, who was among the students killed at Plaza Towers Elementary School during the tornado. Hide Caption 26 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Tara McDonald shows some items salvaged from her home on May 22. Hide Caption 27 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A swing set sits warped at Plaza Towers Elementary School on May 22. Hide Caption 28 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Plaza Towers Elementary School students Monica Boyd and Lavontey Rodriguez sit at the parking lot of their tornado devastated school. Hide Caption 29 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Travis French and his wife, Amy, of Capitol Hill Baptist Church hand out fresh fruit, water and hygiene packs to Thomas and Kelcy Trowbridge. Hide Caption 30 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Teachers from Fairview Elementary School help clean up former school counselor Kay Taylor's home in south Oklahoma City on May 22, two days after an extremely powerful tornado tore through Moore, Oklahoma. Hide Caption 31 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Jake English, 12, cleans up retired school counselor Kay Taylor's home on May 22 in south Oklahoma City, just west of Moore. The storm was part of a tornado outbreak that began in the Midwest and Plains on Sunday, May 19. Hide Caption 32 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A man talks on his cell phone in front of a destroyed house on May 22. Hide Caption 33 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A man looks through a pile of clothing at a roadside relief camp on May 22 in Moore. Hide Caption 34 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Volunteers form a chain to retrieve clothing and other household items on May 22. Hide Caption 35 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Jon Booth moves a piece of debris from his mother's destroyed home across the street from Plaza Towers Elementary School on May 22. Hide Caption 36 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Matt Johnson salvages items from his grandparents' home on Tuesday, May 21. Hide Caption 37 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – An aerial view of the destruction on May 21. Hide Caption 38 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – The storm, which touched down near Newcastle, Oklahoma, spanned 1.3 miles. Some areas along the path were completely flattened. Hide Caption 39 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Two men fold an American flag found in the debris of a house on May 21 in Moore. Hide Caption 40 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A young girl stands among the rubble outside Briarwood Elementary School on May 21. Hide Caption 41 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A doll covered in dirt is among the rubble scattered throughout a neighborhood in Moore on May 21. Hide Caption 42 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Bonnie Lolofie, left, and Ashley Do carry belongings from their apartment, which has no power, on May 21. Hide Caption 43 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Residents salvage belongings from their demolished homes in Moore on May 21. Hide Caption 44 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Kelli Kannady weeps after finding a box of photographs of her late husband in the rubble near where her home once stood in Moore on May 21. Hide Caption 45 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Tufts of pink insulation hang from the rafters of a store in Moore on May 21 that was destroyed in the storm. Hide Caption 46 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Natalie Johnson searches through her mother's destroyed car outside Briarwood Elementary School in Moore on May 21. Hide Caption 47 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Rescuers dig out a house in Moore on May 21. Hide Caption 48 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – June Simson embraces her cat Sammi after she found him standing among the rubble of her destroyed home in Moore on May 21. Hide Caption 49 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A man stands on the roof of a destroyed home in Moore on May 21. Hide Caption 50 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A man helps move a resident's belongings from a destroyed home on May 21 in Moore. Hide Caption 51 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Air Force Airman First Class Justin Acord sifts through the rubble of his father-in-law's home in Moore on May 21. Hide Caption 52 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – People recover belongings from the rubble of a home in Moore. Hide Caption 53 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – People sort through a leveled home in Moore on May 21. Hide Caption 54 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Debris lies among headstones in the Moore Cemetery on May 21. Hide Caption 55 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Workers clean up the Warren movie theater in Moore on May 21. Hide Caption 56 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Oklahoma City Mayor Mick Cornett surveys damage in Moore on May 21. Hide Caption 57 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Piles of debris lie around the north side of Plaza Towers Elementary School in Moore on May 21. Hide Caption 58 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – As dawn breaks, storm clouds roll in over a devastated neighborhood in Moore on May 21. Hide Caption 59 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Members of the Oklahoma National Guard look for survivors in rubble in Moore on May 21. Hide Caption 60 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A National Guardsman assists in the search for victims on May 21. Hide Caption 61 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A rescue worker leads a horse from the wreckage of a day care center and barns on Monday, May 20, in Moore. Hide Caption 62 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Men tie an American flag on debris in a neighborhood off Telephone Road in Moore on May 20. Hide Caption 63 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Children wait for their parents to arrive at Briarwood Elementary School in south Oklahoma City on May 20. Hide Caption 64 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Teachers carry children away from Briarwood Elementary School on May 20. Hide Caption 65 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Teachers lead children away from Briarwood Elementary School on May 20. Read more about the photo. Hide Caption 66 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A fire official drives through the rubble of Moore Medical Center on May 20. Hide Caption 67 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Abby Madi, left, and Peterson Zatterlee comfort Zatterlee's dog, Rippy, on Monday, May 20, in Moore. Hide Caption 68 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A woman is treated for her injuries on May 20 at a triage area set up for the wounded. Hide Caption 69 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Two girls stand in rubble in Moore. Hide Caption 70 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Rescue workers help free one of more than a dozen people who were trapped at a medical center in Moore on May 20. Hide Caption 71 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Oklahoma City firefighters check on Gene Tripp on May 20 as he sits in his rocking chair where his home once stood. Hide Caption 72 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A nurse helps an older man who suffered a head injury on May 20 in Moore. Hide Caption 73 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Cars marked with an orange X, meaning they have been checked for occupants, are piled up in front of the entrance to the damaged Moore Medical Center on May 20. Hide Caption 74 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Jim Routon hugs his neighbor, 7-year-old Hezekiah, after the tornado strikes on May 20. An earlier version of this caption incorrectly stated that Routon was Hezekiah's teacher. See an interview with the pair. Hide Caption 75 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – People look through the wreckage of their neighborhood after a tornado struck Moore, Oklahoma, on May 20. Hide Caption 76 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Dana Ulepich searches inside a room left standing at the back of her destroyed house in Moore on May 20. Hide Caption 77 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Residents look through the debris in Moore on May 20. Hide Caption 78 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A man looks through the remains of a home after the massive tornado struck Moore on May 20. Hide Caption 79 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A woman is transported on a stretcher after she was rescued from the damaged medical center in Moore on May 20. Hide Caption 80 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A woman walks through debris in Moore on May 20. Hide Caption 81 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A man is taken away from the IMAX Theater in Moore that was used as a triage center on May 20. Hide Caption 82 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A girl wraps herself in a blanket near the Moore Hospital on May 20. Hide Caption 83 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A nurse walks by the destruction at a Moore hospital on May 20. Hide Caption 84 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Destroyed cars scatter the landscape in Moore, Oklahoma, where hundreds of homes and buildings were put to ruin on May 20. Hide Caption 85 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A woman with an arm injury is helped on May 20 in Moore. Hide Caption 86 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Extensive damage from the tornado destroyed cars and demolished structures in Moore on May 20. Hide Caption 87 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Onlookers stop to view a portion of the destruction left behind on May 20 in Moore. Hide Caption 88 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Overturned cars are among the rubble from the tornado that hit Moore on May 20. Hide Caption 89 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A woman is comforted after the May 20 tornado in Moore. Hide Caption 90 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A shredded tree stands amid debris in the aftermath of the storm in Moore on May 20. Hide Caption 91 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A shopping center parking lot is covered with debris and damaged cars on May 20. Hide Caption 92 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – Law enforcement officers block a roadway in Moore where there was extensive damage from the tornado. Hide Caption 93 of 94 Photos: Photos: Deadly tornado hits Oklahoma Deadly tornado hits Oklahoma City area – A massive tornado approaches Moore on May 20. The storm first touched down to the west of the city near Newcastle, Oklahoma. Visit CNN.com/impact for ways to help the victims. Hide Caption 94 of 94

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'One of the strongest storms'

Damage assessments conducted Tuesday showed the tornado packed winds, at times, between 200 and 210 miles per hour, making it an EF5 -- the strongest category of tornadoes measured, the National Weather Service said Tuesday.

Teams are still evaluating the destruction, and the rating released Tuesday is preliminary. So far, they've found that the tornado's width spanned 1.3 miles -- the length of more than 22 football fields lined up end-to-end.

Given its breadth and power, it ranks among some of the strongest storms ever to strike the United States, CNN senior meteorologist Dave Hennen said.

Hardest hit was Moore, Oklahoma -- a suburban town of about 56,000 and the site of eerily similar twisters in 1999 and again four years later.

The scene -- block after block of flattened homes and businesses, the gutted remains of a hospital and hits on two elementary schools -- left even seasoned veterans of Oklahoma's infamous tornadoes reeling.

The devastation was so complete, the mayor said city officials were racing to print new street signs to help guide rescuers and residents through a suddenly twisted and unfamiliar landscape.

A search-and-rescue team was sent from nearby Tinker Air Force Base, which also provided search lights, vehicles and water trucks, while neighboring Texas sent an elite 80-member urban search team. The American Red Cross sent 25 emergency response vehicles.

Rescue crews were expected to complete a search for victims by late Tuesday, Moore Fire Chief Gary Bird told CNN.

"We will be through every damaged piece of property in this city at least three times," Bird told reporters. "And we hope to be done by dark tonight."

More than 230 people were injured, according to authorities.

Photos: Photos: Tornadoes strike Midwest Photos: Photos: Tornadoes strike Midwest Tornadoes wreak havoc in Midwest – Rescuers search through rubble in Shawnee, Oklahoma, on Monday, May 20. A tornado outbreak hit in the Midwest and Plains on Sunday and Monday, the deadliest hitting Moore, Oklahoma, on Monday. Hide Caption 1 of 18 Photos: Photos: Tornadoes strike Midwest Tornadoes wreak havoc in Midwest – Massive piles of debris cover the ground after a powerful tornado ripped through Moore, Oklahoma, on May 20. View photos related to the Moore tornado. Hide Caption 2 of 18 Photos: Photos: Tornadoes strike Midwest Tornadoes wreak havoc in Midwest – A deadly tornado destroys cars and demolishes structures in the town of Moore, near Oklahoma City, on Monday, May 20. Hide Caption 3 of 18 Photos: Photos: Tornadoes strike Midwest Tornadoes wreak havoc in Midwest – A volunteer helps clean up a mobile home on May 20 after it was overturned on a day earlier near Shawnee, Oklahoma. Hide Caption 4 of 18 Photos: Photos: Tornadoes strike Midwest Tornadoes wreak havoc in Midwest – Jean McAdams' mobile home near Shawnee, Oklahoma, lies overturned on May 20. Hide Caption 5 of 18 Photos: Photos: Tornadoes strike Midwest Tornadoes wreak havoc in Midwest – President Barack Obama talks on the phone with Oklahoma Gov. Mary Fallin from the Oval Office on May 20. The president expressed his concern for those who have been affected by the severe weather. Hide Caption 6 of 18 Photos: Photos: Tornadoes strike Midwest Tornadoes wreak havoc in Midwest – Tom and Ronda Clark get help with cleanup on May 20, after their property near Shawnee was damaged by a tornado on May 19. Hide Caption 7 of 18 Photos: Photos: Tornadoes strike Midwest Tornadoes wreak havoc in Midwest – Lonnie Langston says his garage was swept off the concrete pad next to his house by a tornado near Shawnee. Hide Caption 8 of 18 Photos: Photos: Tornadoes strike Midwest Tornadoes wreak havoc in Midwest – Shawnee residents embrace on May 20 as they search through the remains of their home. Hide Caption 9 of 18 Photos: Photos: Tornadoes strike Midwest Tornadoes wreak havoc in Midwest – A home in Shawnee sits in ruin after being hit by a tornado on Sunday, May 19. Hide Caption 10 of 18 Photos: Photos: Tornadoes strike Midwest Tornadoes wreak havoc in Midwest – A twister stretches toward the ground near South Haven, Kansas, on May 19. Hide Caption 11 of 18 Photos: Photos: Tornadoes strike Midwest Tornadoes wreak havoc in Midwest – Residents repair the roof of a neighbor's damaged house after a tree fell on it in Shawnee on May 19. Hide Caption 12 of 18 Photos: Photos: Tornadoes strike Midwest Tornadoes wreak havoc in Midwest – A woman waits to be allowed back to her home after a tornado swept through Shawnee on May 19. Hide Caption 13 of 18 Photos: Photos: Tornadoes strike Midwest Tornadoes wreak havoc in Midwest – Storm chaser and videographer Brad Mack records a tornado touchdown in South Haven, Kansas, on May 19. Hide Caption 14 of 18 Photos: Photos: Tornadoes strike Midwest Tornadoes wreak havoc in Midwest – A tractor-trailer lies on its side on Interstate 40 while another is broken open on the road below after falling from the overpass after a tornado strike near Highway 177 north of Shawnee on May 19. Hide Caption 15 of 18 Photos: Photos: Tornadoes strike Midwest Tornadoes wreak havoc in Midwest – A tornado touches down near Wichita, Kansas, on Sunday, May 19. Hide Caption 16 of 18 Photos: Photos: Tornadoes strike Midwest Tornadoes wreak havoc in Midwest – Debris from a mobile home park west of Shawnee litters the ground on May 19. An estimated 300 homes were damaged or destroyed across Oklahoma, Red Cross spokesman Ken Garcia said. Hide Caption 17 of 18 Photos: Photos: Tornadoes strike Midwest Tornadoes wreak havoc in Midwest – Lightning strikes in Clearwater, Kansas, on May 19. Hide Caption 18 of 18

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'Can't believe this'

Some residents of Moore returned home to piles of debris, hoping to find pictures or some memento.

"You just wanna break down and cry," Steve Wilkerson told CNN, holding a laundry basket that contained the few, intact belongings he could find.

"But you know, that's how it goes," Wilkerson said, his voice shaking. "You gotta be strong and keep going."

Wilkerson has been through tornadoes before, but nothing like this one.

"I still can't believe this is happening," he said. "You work 20 years, and then it's gone in 15 minutes."

All that remained in some places were "sticks and bricks," Fallin told reporters, calling the storm one of the "most horrific storms and disasters that this state has ever faced."

Police, firefighters, volunteers and nearly 180 National Guard troops joined forces Tuesday in searching the rubble and securing areas hit by the storm.

The weather wasn't cooperating with their efforts: National Weather Service crews surveying the damage in Moore reported rain, half-inch hail and 45-mph winds over the debris field.

The Oklahoma Highway Patrol asked motorists to steer clear of Interstate 35 near Moore to free up lanes for disaster response resources streaming into the area.

And so many people were showing up to volunteer that authorities had to plead with would-be rescuers to stay away.

Path of devastation

The tornado struck at 2:45 pm C.T. on Monday -- only 5 minutes after the first warnings went out, according to the National Weather Service.

Moore residents had about 30 minutes before the massive storm entered the western part of the city, CNN meteorologist Sean Morris said.

Among the many buildings struck by the storm were two schools: Plaza Towers and Briarwood elementaries.

Of the nine children killed by the storm, authorities said seven died at Plaza Towers Elementary School where the tornado ripped the roof off and collapsed walls.

Among the dead is 9-year-old Ja'Nae Hornsby, who was killed at Plaza Towers, her father told CNN's Anderson Cooper.

About 75 students and staff members were hunkered down in Plaza Towers when the tornado struck, CNN affiliate KFOR reported.

At one point, an estimated 24 children were missing from the school, but some later turned up at nearby churches.

On Monday, a father of a third-grader still missing sat quietly on a stool outside. Tears cascaded from his face as he waited for any news.

Even parents of survivors couldn't wrap their minds around the tragedy.

"I'm speechless. How did this happen? Why did this happen?" Norma Bautista asked. "How do we explain this to the kids? ... In an instant, everything's gone."

'It's heartbreaking'

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James Dickens, a gas-and-oil pipeline worker, grabbed his hard had and joined other rescuers at Plaza Towers Elementary School.

"I felt it was my duty to come help," he said Tuesday after a long night of searching.

"As a father, it's humbling. It's heartbreaking to know that we've still got kids over there that's possibly alive, but we don't know."

Moore, and the Oklahoma City region, are far too familiar with disaster. In 1995, 168 people died in the bombing of the Alfred P. Murrah Federal Building in Oklahoma City.

In 1999 and then again in 2003, Moore took direct hits from tornadoes that took eerily similar paths to Monday's storm. The 1999 storm packed the strongest wind speeds in history, Lt. Gov. Todd Lamb said.

"We're a tough state. This is a tough community," Lamb said. "There is hope. We always have hope. We always have faith."

President Barack Obama, pledging whatever federal aid Oklahoma would need, praised teachers who protected their students.

"If there is hope to hold on to -- not just in Oklahoma but around the country -- it's the knowledge that the good people there and in Oklahoma are better prepared for this type of storm than most," he said. "And what they can be certain of is that Americans from every corner of this country will be right there with them, opening our homes, our hearts, to those in need, because we're a nation that stands with our fellow citizens as long as it takes."

More trouble brewing

The storm system that spawned Monday's tornado and several other twisters Sunday isn't over yet.

Southwest Arkansas and northeast Texas, including Dallas, are under the gun for severe weather Tuesday. Those areas could see large hail, damaging winds and tornadoes.

A broader swath of the United States, from Texas to Indiana and up to Michigan, could see severe thunderstorms.

"We could have a round 3," CNN meteorologist Ivan Cabrera said. "Hopefully, it won't be as bad."