IS militants are thought to have killed up to 500 people — Iraqi civilians and soldiers — and forced 8,000 to flee from their homes as they captured the city of Ramadi, a provincial official said.

Iraq’s armed forces, backed by Shi’ite militia, attacked Islamic State (IS) strongholds north of Baghdad yesterday as they launched an offensive to retake the city of Tikrit and the surrounding Sunni Muslim province of Salahuddin.