Experts speculated that the Ukrainian aircraft could have collided with a military drone before crashing.
Ilya Kusa, a Ukrainian international affairs expert, said amid the US-Iranian tensions “there were lots of them in the sky immediately after the rocket attacks.
“They are small, difficult to notice.”
He said: “It is difficult not to connect the plane crash with the US-Iran confrontation.
“One must understand that this happened shortly after Iran’s missile attacks on US military facilities.
“Everyone was tense, expecting continued shelling.”
Honoured Russian military pilot Vladimir Popov said: “It could have been an unmanned reconnaissance aircraft, which are small in size and poorly visible on radars.
“A plane in a collision could get significant damage and even catch fire in the air."
The experts said both Iranian and US drones were in the air at the time.
However, Iranian and Ukrainian experts say the main version is a technical glitch with the plane soon after takeoff from Tehran.
Photo source: picture from an open source