Authorities in Kazakhstan are investigating the cause of an Azerbaijan Airlines plane crash in the country, which killed 38 people and injured 29 others on Christmas Day.The big picture: Flight J2-8243 was diverted while en route from Baku,

"Those responsible must be punished, brought to criminal responsibility, and compensation must be paid," President Ilham Aliyev said.

The leader of Azerbaijan criticized the Russian response to the crash of a passenger jet that Azerbaijani officials said had most likely been hit by Russian air defenses.

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.

Russian President Vladimir Putin apologized for the “tragic incident,” which left 38 people dead, though he stopped short of taking responsibility.

Four sources with knowledge of the preliminary findings of Azerbaijan's investigation told Reuters that Russian air defences mistakenly shot it down.

Azerbaijan’s President Ilham Aliyev has accused Russia of accidentally shooting down an airliner on Christmas Day in a disaster that killed 38 people, and covering up the cause.

Azerbaijan's president has accused Russia of shooting down a plane that recently crashed under controversial circumstances. The allegation comes amid heightened tensions in the region, with both countries exchanging accusations over security and sovereignty issues.