Azerbaijan on Sunday paid tribute to the pilots and passengers of the Azerbaijan Airlines passenger plane that crashed in Kazakhstan killing 38 people after Russian air defences were used against Ukrainian drones.

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

Russian President Vladimir Putin apologized to the President of Azerbaijan for the crash of the civilian airliner that killed 38 people, the Kremlin said Saturday.