AL-UDEID AIR BASE, Qatar — The U.S.-led coalition fighting the Islamic State group says an airstrike on a mosque in Syria last week targeted an insurgent command and control center and killed a dozen fighters.

The coalition said in a statement Sunday that while the law of war protects mosques, the use of the building as a headquarters by ISIS caused it to lose that protected status.

Syrian state media and the Britain-based Syrian Observatory for Human Rights said last week that a series of strikes in Sousa near the Iraq border killed and wounded dozens; civilians as well as ISIS fighters.

The coalition’s statement, focused on the mosque, said monitoring of the building “made us aware” of when only ISIS fighters were present and the strike took place Thursday when it was being used to coordinate attacks on the coalition and on U.S.-backed Syrian Democratic Forces. Sousa is in the last ISIS-held pocket in Syria and Syrian Democratic Forces have been on the offensive for weeks trying to clear the area of the extremists.

The statement did not acknowledge or refute the reports of civilian deaths from coalition airstrikes in the area. "We conduct inquiries into all credible allegations of civilian casualties," it said.

ISIS fighters recently stormed a settlement for displaced people in the area and kidnapped 130 families.