A Russian airliner carrying 224 passengers crashed into a mountainous area of Egypt's Sinai peninsula on Saturday shortly after losing radar contact near cruising altitude, killing all aboard.

A militant group affiliated to Islamic State in Egypt, Sinai Province, said in a statement it had brought down the plane "in response to Russian airstrikes that killed hundreds of Muslims on Syrian land", but Russia's Transport Minister told Interfax news agency the claim "can't be considered accurate".

The Airbus A321, operated by Russian airline Kogalymavia under the brand name Metrojet, was flying from the Red Sea resort of Sharm el-Sheikh to St Petersburg in Russia when it went down in central Sinai soon after daybreak, the aviation ministry said.

"I now see a tragic scene," an Egyptian security officer at the site told Reuters by telephone. "A lot of dead on the ground and many who died whilst strapped to their seats.

"The plane split into two, a small part on the tail end that burned and a larger part that crashed into a rockface. We have extracted at least 100 bodies and the rest are still inside," the officer, who requested anonymity, said.

Egyptian and Russian authorities said it was too early to draw any conclusions about the cause of the crash.

Bodies were being removed from the scene and transported to various hospitals with 34 arriving in the Zeinhom morgue in Cairo early in the evening.

Islamic State, in a statement on Twitter, said it had brought down the aircraft. "You who kill will be killed."

Russia, an ally of Syrian President Bashar al-Assad, launched air raids against opposition groups in Syria including Islamic State on Sept. 30.

Security sources said they had no indication the Airbus had been shot down or blown up. But in an illustration of sensitivity of the crash, Egypt invited Russian authorities to take part in the investigation.

Sinai is the scene of an insurgency by militants close to Islamic State, who have killed hundreds of Egyptian soldiers and police and have also attacked Western targets in recent months. Much of the Sinai is a restricted military zone.

Islamist fighters in Sinai are not believed to have missiles capable of hitting a plane at 30,000 feet. Islamic State websites have in the past claimed responsibility for actions that have not been conclusively attributed to them.