Russian defence ministry said a Mi-8 helicopter belonging to the government, and with five people on board, was shot down in Syria’s North-Western Idlib province, on Monday.
The ministry said the helicopter was returning to the Khmeimim air base on Syria’s coast after delivering humanitarian aid to the city of Aleppo when it was shot down by fire from the ground.
It said the fate of the three crew members and two officers from Russia’s centre for reconciliation of the Syrian conflict was unknown.
It observed that photos circulated by a pro-rebel news channel on the Telegram messaging application, popular in Syria, purported to show a Russian military man being dragged on the ground after the helicopter crash.
Russia announced last week that it was beginning a large-scale humanitarian operation in Syria’s northern city of Aleppo.
The country has been supporting its long-time ally, Syria, with a military campaign since last year in an effort to restore stability to the country.