There are early indications that a Russian anti-aircraft system may have struck the Azerbaijan Airlines plane that crashed in Kazakhstan, a U.S. official told ABC News.

By Nailia Bagirova and Gleb Stolyarov BAKU (Reuters) -Russian air defences downed an Azerbaijan Airlines plane that crashed in Kazakhstan, killing 38 people, four sources with knowledge of the preliminary findings of Azerbaijan's investigation into the disaster told Reuters on Thursday.

The Azerbaijan Airlines Embraer 190 flight left Baku, Azerbaijan, on Christmas to Grozny, Russia. Instead, the plane crashed in Aktau, Kazakhstan.

The flight was en route from the Azerbaijani capital of Baku to Grozny, in Russia’s south, when it diverted and attempted an emergency landing in Kazakhstan.

The investigation on the crash of the Embraer E190 while attempting an emergency landing is still ongoing, however reports of a possible involvement of

"No one claims that it was done on purpose," an Azerbaijan official told Reuters. They added their government "expects the Russian side to confess."

We will never forget the beloved people we lost in the crash of the Embraer 190 aircraft,” said Azerbaijan Airlines in a statement posted online on Boxing Day. The pro-government AnewZ news station cited Azerbaijan officials as saying shrapnel from a Russian missile was responsible.

BAKU (Reuters) -Russian air defences downed an Azerbaijan Airlines plane that crashed in Kazakhstan, killing 38 people, four sources with knowledge of the preliminary findings of Azerbaijan's investigation into the disaster told Reuters on Thursday.

Questions were being asked Thursday about the cause of an airliner crash in Kazakhstan the day before, as Azerbaijan held a day of mourning for the dozens of victims of the disaster. The reasons that Azerbaijan Airlines flight J2-8243 came down are still unknown.

The Azerbaijan Airlines plane that crashed near Kazakhstan's Aqtau on Christmas Day - while en route from Baku to Grozny in Russia - may have been "accidentally struck" by a Russian surface-to-air missile or antiaircraft fire.

The official cause of the crash of a Russia-bound Azerbaijani plane in Kazakhstan on Wednesday that killed 38 of the 67 people on board is still unknown.