French and Russian air strikes in northern Syria have killed at least 33 jihadists with the Islamic State group in the last 72 hours, a monitoring group said on Wednesday.

Dozens of IS fighters were also wounded in the raids on Sunday, Monday and Tuesday focused on the jihadists' de facto Syrian capital of Raqa, said Rami Abdel Rahman, director of the Syrian Observatory for Human Rights, after strikes intensified following last week's attacks in Paris.