Syria is almost completely cut off from the global Internet.

Several Internet monitoring companies reported Thursday that Syria suffered an almost complete Internet shutdown. This is the latest in a long series of Internet blackouts in the war-torn country.

The blackout started around 8:30 a.m. ET, according to Internet monitoring firm Renesys, which first spotted the outage. Renesys reported that 84 networks experienced an outage in Syria starting at 12:26 UTC, which is 95% of the routed networks in the country, the company wrote.

Internet in Syria almost entirely down at 12:26 UTC. Only Aleppo link to Turkey remains connected. pic.twitter.com/o6flIEbkVy — Renesys Corporation (@renesys) March 20, 2014

The disruption was then confirmed by other companies like Akamai, BGPmon, OpenDNS, and Google.

Near complete Internet disruption in #Syria detected by @Akamai traffic monitoring, starting at ~12:30pm UTC pic.twitter.com/MqGovceSHy — StateOfTheInternet (@akamai_soti) March 20, 2014

Country wide Internet outage in Syria starting at 12:25 UTC Only remaining network are the Aleppo, AS24814, prefixes pic.twitter.com/s74fStmBEz — BGPmon.net (@bgpmon) March 20, 2014

Looks like Syria is offline again. pic.twitter.com/F1eovuPjnE — Think Umbrella (@ThinkUmbrella) March 20, 2014

At this point, the source of the outage is still unclear. In the past, the government has often blamed technical issues — claims that experts meet with skepticism, arguing that the outages seem to coincide with important military operations or offensives, instead indicating that the government might purposely shut down the Internet. This is possible thanks to Syria's stranglehold over the country's single point of failure, the state-controlled Syrian Telecommunications Establishment, which controls the flow of the Internet in and outside of the country.

Doug Madory, a researcher at Renesys, said that only the link from Aleppo to Turkey remains working, something that "is consistent with outages over the past few months."

"Aleppo's outages occur independently from the country-wide blackouts," he added.

The last Internet blackout in Syria was reported Feb. 20, 2014.

UPDATE, 3.31 p.m. ET: The Internet has apparently been restored in Syria, after a blackout that lasted more than 7 hours, according to Renesys and Akamai.

Apparent restoration of #Syria Internet connectivity detected by @Akamai traffic monitoring at ~7:00pm UTC. pic.twitter.com/eQnRJvE1Ho — StateOfTheInternet (@akamai_soti) March 20, 2014

The outage was caused by "a breakdown in the optical fiber cable in Damascus Countryside," according to the Syrian government-owned news agency SANA.

Madory, the Renesys researcher, told Mashable that from the outside world, it's impossible to know for sure what caused the outage, and whether the government's explanation is accurate. But its explanation is plausible.

"If they have a single fiber line that connects Tartous with [Syrian Telecommunications Establishment]'s central office in Damascus and that was what was cut, then this is possible," he said.