A Russian military adviser was killed by mortar fire in Syria on February 1, the Russian Defense Ministry has said.

Russia's Novaya Gazeta reported on February 4 that the adviser died in a hospital in Syria after sustaining serious wounds in a shelling of a Syrian Army training center in the province of Homs by the Islamic State (IS) militant group, citing Defense Ministry spokesman Igor Konashenkov.

Konashenkov told the newspaper that four Syrian Army cadets were also killed in the same mortar shelling.

The ministry said the officer will be posthumously awarded a medal, but didn't identify him or specify where he died.

The officer's death is the third in combat the Russian military has reported since it launched its air campaign in Syria in September.

A Russian pilot whose warplane was downed by a Turkish fighter at the Syrian border was shot dead by militants as he descended by parachute on November 24.

His crewmate survived and was evacuated to safety, but a Russian marine was killed in action during the rescue mission.

Besides sending an unknown number of military advisers to Syria, Russia has deployed ground troops to guard the Russian air base in the coastal province of Latakia.

Based on reporting by AP, Reuters, and TASS