BEIRUT: Air strikes carried out by French jets and other forces have killed at least 33 Islamic State militants in the group's Raqqa stronghold in Syria over the past three days, the Syrian Observatory for Human Rights monitoring group said on Wednesday.

Citing activists, the Observatory also said that Islamic State members and dozens of the families of senior members had started leaving Raqqa city to relocate to Mosul in Iraq because of security concerns. Mosul is also controlled by Islamic State.