Russias Defense Ministry said Thursday that one of its warplanes, an advanced multi-role fighter jet, has crashed in the Mediterranean Sea off Syria and that both pilots aboard were killed. State news agency Tass cited the ministry as saying the Su-30 crashed on Thursday morning while climbing after takeoff from the Russian airbase at Hmeimim in Syria’s Latakia Province. The ministry said the plane did not come under fire and that preliminary information indicates the crash could have been caused by a bird being sucked into one of the planes engines. “According to preliminary information, the reason for the aviation disaster could have been birds getting into the engine," it said. The most recent acknowledged Russian military loss came when a transport plane crashed on landing at the Hmeimim airbase in March, killing all 39 people on board.