Russias defense ministry on Thursday said two servicemen were killed in a mortar attack by militants in Syria on New Years Eve, but denied a report by Russian daily Kommersant that seven military planes were destroyed.  "As darkness fell, the Hmeimim air base was subjected to sudden mortar shelling from a mobile group of militants. As a result of the shelling, two servicemen were killed," the defense ministry said in a statement to Russian agencies. Kommersant reported seven military planes had been "practically destroyed" in the attack, citing two military-diplomatic sources. At least four Su-24 bombers, two Su-35S fighters and an An-72 transport plane, as well as an ammunition depot, were destroyed by the shelling, the newspaper said on its website. But the ministry said the report was "fake". The new developments come a day after the ministry announced a Russian Mi-24 helicopter crash in Syria that killed two pilots following a technical fault, also on December 31.  With four fatalities this is one of the deadliest single days for the Russian army in Syria since it entered the conflict and brings the total number of officially reported losses to 44.  Security around the Hmeimim base was being stepped up after the mortar attack, the defense ministry said. "The Russian air force in Syria is combat-ready and continues to fulfill all intended tasks," the statement added.