"On August 1, an Mi-8 transport helicopter has been shot down by ground fire in Idlib province after a delivery of humanitarian aid to the city of Aleppo. Three crew members and two officers from Russia's reconciliation center in Syria were on board," the Defense Ministry said in a statement.
"Those on board the helicopter were killed, they died heroically as they tried to divert the helicopter to minimize casualties on the ground.
The helicopter was said to be returning to the Russian air base at Khmeimim, the statement added. The ministry has not yet revealed the identities of those on board.
The Russian air base at Khmeimim has operated since February. It contributes to peace talk between to peace talks between Syria Government and moderate opposition groups not aligned to with IS terrorist.