The Russian Defense Ministry says a military plane has crashed in Syria, killing two pilots aboard.
A Sukhoi-30 fighter jet crashed shortly after taking off from Hmeimim air base in Syria's Latakia Province on May 3, the ministry said in a statement, adding that the plane had not been shot down.
Several Russian agencies quoted unnamed ministry officials as saying preliminary investigations show the crash might have been caused by a bird strike.
Russia has more than 50 fighter jets and helicopters in Syria and a contingent of ground forces protecting them, along with a number of consultants and special forces operating with the Syrian military.
Russia and Iran have been supporting Syrian leader Bashar al-Assad's government in the seven-year civil war.
Moscow helped turn the tide of the conflict in Assad's favor by launching a campaign of air strikes in 2015 and stepping up its military presence on the ground.