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.

"No one claims that it was done on purpose," an Azerbaijan official told Reuters. They added their government "expects the Russian side to confess."

The Kremlin urged restraint on Thursday in speculating about the cause of an Azerbaijan Airlines plane crash in Kazakhstan that killed 38 of the 67 passengers on board. "An investigation is currently under way;