(CNN)U.S. helicopter gunships supported Iraqi ground forces battling ISIS militants in al-Baghdadi, military sources said, an action that brings U.S. troops closer to combat. On Saturday, the U.S. military said al-Baghdadi was "contested," as Iraqi forces fought back. The U.S. military Friday deployed attack helicopters against an ISIS assault on the strategic Ayn al-Assad Air Base about 15 kilometers (9 miles) south of al-Baghdadi, sources said. Iraqi ground forces killed those attackers and the Apaches safely returned to base without firing a shot, the source said. Robert Baer, a former CIA officer, said the battles may indicate a deepening involvement of U.S. troops in the fight against ISIS.
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U.S. helicopter gunships support Iraqi troops battling ISIS, military sources say
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It's unclear whether militants got past the perimeter of the base housing U.S. forces, a Pentagon spokesman says
Most, if not all, of the attackers were wearing @placeholder military uniforms, Kirby said.