Story highlights Kyriakos Amiridis was appointed ambassador in January, Agencia Brasil reports

His remains were found inside a burned car this week, police say

The widow's paramour is accused of carrying out the killing

(CNN) Police contend Greece's ambassador to Brazil was killed by his wife's lover -- a military police officer -- and the widow is being questioned in the crime, Brazil's state-run Agencia Brasil news agency reported Saturday.

Chief Evaristo Pontes, a police investigator in the Baixada Fluminense region, said Friday that Sergio Gomes Moreira Filho claimed he killed the ambassador in self-defense and then recruited his cousin to help dispose of the body, Agencia Brasil News reported.

Ambassador Kyriakos Amiridis, 59, had been missing since Monday, Pontes said. A burned car with Amiridis' charred body inside was found in Nova Iguaçu, a town outside Rio de Janeiro, on Thursday, he said.

"He (Moreira) says he got into a physical fight with the ambassador, and he had no choice other than to hit the ambassador and kill him," Pontes said. "He says he was in desperation and didn't know what to do, given what had happened, so he asked a cousin for help and they went to make the ambassador's body disappear."

Greek ambassador to Brazil Kyriakos Amiridis.

Besides Moreira, the ambassador's widow, Francoise De Souza Oliveira, and the officer's cousin, Eduardo Moreira de Melo, are also being questioned, Pontes said.

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