T hursday is an official day of mourning in Azerbaijan as an investigation is underway to determine what caused an airplane carrying 67 passengers to crash on Christmas Day in Kazakhstan, killing 38 and leaving at least 29 survivors. Video posted by CNN shows the plane crash-landing, exploding into a fireball and plumes of black smoke.

Mobile phone footage circulating online appeared to show the aircraft making a steep descent before smashing into the ground in a fireball. Some of the videos posted on social media showed survivors dragging fellow passengers away from the wreckage.