In this photo made from video released from Russian Defense Ministry, Russian air force Tu-22M3 bombers drop bombs on a target in Syria.

Russia has bombed the Islamic State group in the heaviest strikes in eastern Syria since the war began.

Moscow's military manoeuvres in the Mediterranean even forced Lebanon to reroute flights.

The Syrian Observatory for Human Rights says Russian and Syrian warplanes carried out more than 70 strikes in eastern Deir Ezzor province on Friday killing at least 36 people including 10 children.