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.

The Azerbaijan Airlines Embraer 190 flight left Baku, Azerbaijan, on Christmas to Grozny, Russia. Instead, the plane crashed in Aktau, Kazakhstan.

An Azerbaijan Airlines Embraer 190 was en route from Azerbaijan's capital of Baku to the Russian city of Grozny when it crashed, killing 38 people onboard.