BAGHDAD: An international aid organisation says the Islamic State group is targeting civilians and shooting them as they try to flee the fighting between Iraqi government forces and IS militants in Fallujah, west of Baghdad.

The Norwegian Refugee Council, which works with refugees and internally displaced Iraqis, says IS militants have opened fire on civilians trying to cross the Euphrates River and that a number of them have been killed. The NRC cited interviews with some of those who fled in its report late Sunday.

Iraqi forces, backed by US-led coalition airstrikes, are fighting to retake the IS-held city of Fallujah but the operation has stalled since last week because of heavy fighting that the militants have put up and because of an estimated 50,000 civilians trapped inside the city.