The jet crashed near the Kazakh city of Aktau on Wednesday, killing 38 of the 67 people on board, after attempting to land at its destination in the Russian city of Grozny and then diverting far off course across the Caspian Sea.

Russia’s aviation chief said on Friday that Grozny was being attacked by Ukrainian drones at the time the plane had tried to land, but the Kremlin has declined to comment on reports the plane was accidentally shot down by Russian air defence missiles.

Statements from Azerbaijan citing the investigation into the incident suggest Baku believes the plane was hit mid-air.

“Based on the opinion of experts and on the words of eyewitnesses, it can be concluded that there was external interference,” Azerbaijani’s transport minister, Rashad Nabiyev, told reporters.

“It is necessary to find out from what kind of weapon,” he added, citing reports from survivors of hearing “three explosions” as the plane was over Grozny.

Azerbaijan Airlines said it had suspended flights to 10 Russian airports, saying preliminary results suggested the crash of Baku-Grozny flight J2-8243 was “due to physical and technical external interference”.

The head of Russia’s civil aviation agency, Dmitry Yadrov, said in an earlier statement that “the situation on this day and at these hours in the area of Grozny airport was very complex”.

“Ukrainian attack drones at this time were making terrorist attacks on civilian infrastructure in the cities of Grozny and Vladikavkaz,” Yadrov said, referring to a nearby city.

He said the Azeri pilot made “two attempts to land the plane in Grozny that were unsuccessful” in “thick fog”.

“The pilot was offered other airports. He took the decision to go to Aktau airport,” he added.