Islamic State fighters have taken control of a large part of the western Iraqi town of al-Baghdadi. The town is only 15 minutes away from the Ain al-Asad air base where U.S. Marines are training Iraqi troops.
Pentagon officials stress that the U.S. Marines have not been involved in the fighting or have any of then been captured or wounded by Islamic State fighters.
Al-Baghdadi, about 85 km (50 miles) northwest of Ramadi in Anbar province, has been besieged for months by the radical Sunni Islamist militants who captured vast swathes of northern and western Iraq last year.
Militants attacked al-Baghdadi from two directions earlier in the day and then advanced on the town, intelligence sources and officials in the Jazeera and Badiya operations commands said.
The officials said another group of insurgents then attacked the heavily-guarded Ain al-Asad air base five km southwest of the town, but were unable to break into it.
About 320 U.S. Marines are training members of the Iraqi 7th Division at the base, which has been struck by mortar fire on at least one previous occasion since December.
Pentagon spokeswoman Navy Commander Elissa Smith did confirm that was "heavy fighting" in al-Baghdadi.
“There was no direct attack on the Al Asad air base. There were reports of ineffective indirect fire in the vicinity of the base.
“We continue to support efforts by Iraqi Security Forces, working in conjunction with tribal fighters, directed against ISIL in the province,” Smith said.