Azerbaijan held a day of mourning on Thursday for the dozens of victims of an airliner crash in Kazakhstan, as questions were being asked over the cause of the disaster.

Russian aviation authorities said the Azerbaijan Airlines plane had hit a flock of birds. But some experts cast doubt on that account, pointing to footage showing apparent holes in the fuselage.

According to Euronews sources, the crash of the Azerbaijan Airlines plane flying from Baku to Grozny on 25 December was caused by a Russian surface-to-air missile that exploded nearby. Source: Euronews Quote: "Sources in the Azerbaijani government confirmed in an exclusive statement to Euronews on Thursday that a Russian surface-to-air missile was the cause of the crash of an Azerbaijani Airlines plane in Aktau on Wednesday.