Several passenger plane crashes have occurred worldwide this year, including a Wednesday morning Azerbaijan Airlines wreck that has left dozens feared dead.

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

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.

Russian President Vladimir Putin on Saturday apologized to his Azerbaijani counterpart for what he called a “tragic incident” following the crash of an Azerbaijani airliner in Kazakhstan that killed 38 people,

President Vladimir Putin on Saturday apologised to Azerbaijan’s leader for what the Kremlin called a “tragic incident” over Russia in which an Azerbaijan Airlines plane crashed after Russian air defences were fired against Ukrainian drones.

President Putin apologised “for the fact that the tragic incident occurred in Russian airspace” stopped short of admitting responsibility for the incident