The jet was en route from the country's capital Baku to the city of Grozny in Chechnya, southern Russia, on Wednesday but crashed near Aktau in Kazakhstan.

Euronews cited Azerbaijani government sources as saying that "shrapnel hit the passengers and cabin crew as it exploded next to the aircraft mid-flight".

Military and aviation experts have pointed to apparent shrapnel damage on the fuselage of the plane.

Euronews also cited its sources saying the damaged plane "was not allowed to land at any Russian airports despite the pilots' requests for an emergency landing".

They said the plane was instead ordered to fly across the Caspian Sea to Aktau -- far off its original route.

Turkey's official Anadolu news agency carried a similar report citing the preliminary results of the investigation, saying "the plane was attacked by a Pantsir missile system" as it approached Grozny.

Ukrainian drone strikes have been registered in Chechnya in recent weeks, and there was reported drone activity in nearby Ingushetia and North Ossetia before the crash.

"The aircraft's communication system was completely paralysed due to the use of Russian electronic warfare systems, which resulted in the plane disappearing from radars while in Russian airspace," Anadolu reported.

The New York Times reported that "two Azerbaijanis briefed on a government inquiry said that Azerbaijani officials now believe that a Russian Pantsir-S defence system damaged the plane".

Azerbaijan Airlines initially said the plane flew through a flock of birds before withdrawing the statement.

Russia's aviation agency also mentioned birds as a possible cause.

The specialist website Flightradar24 said the flight had experienced "significant GPS interference".

It said the plane "stopped sending positional data" for a few minutes.

The plane was carrying 62 passengers and five crew members.

Kremlin spokesman Dmitry Peskov earlier on Thursday cautioned against "hypotheses" about the crash before the official Kazakh investigation is completed.

bur/dt/js

THE NEW YORK TIMES COMPANY