The United States calculates there are up to 10,000 ISIS fighters in Iraq and Syria . It wants to establish a caliphate , or Islamic state , that would stretch into both countries . Iraq : At least 100 civilians were killed during the government 's campaign in northern Iraq .
The United States calculates there are up to 10,000 ISIS fighters in Iraq and Syria . ISIS wants to establish a caliphate , or Islamic state , that would stretch into both countries . UN : At least 757 civilians were killed during the group 's advance in northern Iraq .