Cairo: International investigators today began probing the crash of a Russian Airbus plane in Egypt's Sinai Peninsula that killed all the 224 people on board as black boxes were recovered and sent for analysis amid claims by an Islamic State-affiliate group that it downed the jet.

The Islamic State-affiliate group in Egypt, which is waging a deadly insurgency in the Sinai, claimed it downed the plane in the mountainous area of the Sinai Peninsula but Cairo and Moscow both rejected the claim.