Experts say evidence in the Azerbaijan Airlines plane crash in Kazakhstan points to a possible midair explosion, not an encounter with a flock of birds.

The Kremlin said Putin had "offered his apologies that the tragic incident had occurred in Russia's airspace."

Russian President Vladimir Putin acknowledged a role in the crash of an Azerbaijan Airlines plane carrying 67 people, but stopped short of expressing responsibility.

Russian President Vladimir Putin said Saturday that Russia’s air defense systems were active when an Azerbaijan Airlines flight attempted to land in Grozny, Chechnya on Wednesday.

Russia's aviation watchdog said the captain of the plane had been offered other airports at which to land, but had chosen Kazakhstan's Aktau.

Russia has published a festive video of Santa Claus becoming a victim of Russian air defence against the backdrop of the tragic crash of an Azerbaijan Airlines passenger plane in Grozny, with growing evidence pointing to Russian air defence as the cause.

Kazakhstan, Azerbaijan and Russia all opened investigations into the cause of the crash of Azerbaijan Airlines Flight 8243.

Several airlines have announced the suspension of flights to Russian cities, after an Azerbaijan Airlines plane with 67 people on board crashed.

The White House said Friday there were "early indications" that Russian air defenses downed an Azerbaijan Airlines flight in Kazakhstan.

The Kremlin on Thursday warned against speculating about what may have caused an Azerbaijan Airlines flight to crash, killing 38 of the 67 people on board, after an aviation expert said evidence indicated that a Russian anti-missile battery may have brought down the passenger plane.

Azerbaijan Airlines has suspended flights to multiple Russian airports in the wake of a deadly plane crash, which it attributed to "physical and technical external interference."