Sinai plane crash
Egyptian paramedics load the corpses of Russian victims of a passenger plane crash in the Sinai Peninsula into a military planeKhaled Desouki/AFP/Getty Images

The Islamic State (IS) has claimed it downed a Russian plane that crashed in Egypt despite early evidence suggesting a technical failure was to blame for the deadly incident. Flight 7K9268 from the Red Sea resort of Sharm el-Sheikh to St Petersburg came down in the Hassana area of the restive Sinai peninsula, where the jihadi group's local offshoot has been leading an insurgency against the government.

All 224 people on board the Airbus A321 operated by Russian airline Kogalymavia were killed. Hours after the disaster, IS supporters circulated a French and Arabic statement from the group on social media.

"Soldiers of the Caliphate were able to down a Russian plane above Sinai Province," the statement read. The message referred to the passengers as "Crusaders" and linked the incident to Moscow's military intervention in support of the regime of Bashar al-Assad in Syria.

The claim has been largely dismissed as unsubstantiated terror propaganda. IS didn't offer any clue regarding how it shot down the aircraft and the group is not known to have the capability to do so. Russian transport minister Maxim Sokolov told Interfax news agency there was no evidence it was a terrorist attack. "Such reports cannot be considered true," he said.

Many analysts expressed doubts about IS involvement on Twitter.

The plane was travelling at about 35,000 feet when it started a rapid descent. IS Egyptian branch, a militant group previously known as Ansar Beit al-Maqdis and successfully renamed only as Sinai Province, was reported to have MANPADS, portable air-defence weapons, that can shoot down aircraft travelling only at up to 22,000 feet.

Egyptian authorities have also said that early indications suggest a technical failure was to blame. Russian media reported the crew had complained the aircraft put into service 18 years ago experienced engine problems several times before its last flight.

Shortly after take-off, the pilot radioed he had technical issue on board and asked to make an emergency landing at El Arish airport, in northern Sinai, but crashed before being able to reach it, the Russian embassy in Cairo said.

Egypt and Russia have launched an investigation into the disaster, pledging to cooperate closely. More details on what could have caused the crash will be provided by the flight's black box that has already been located by investigative teams at the scene.