U.S. soldiers killed 14 insurgents in two days of fighting in a strategic northern city, the American military said Monday, and gunmen killed 10 Iraqi soldiers in the central Sunni heartland. Soldiers of the U.S. 3rd Armored Cavalry Regiment killed four insurgents in a gunbattle Sunday, and 10 more were killed Monday as fighting raged in Tal Afar, 260 miles north of Baghdad, the U.S. command reported. American troops suffered no casualties, the statement said.However, insurgents bloodied an Iraqi force in Khalis, 45 miles north of Baghdad. Guerrillas firing mortars, machine guns and semiautomatic weapons stormed an Iraqi checkpoint about 5 a.m., killing eight Iraqi soldiers, Khalis police chief Col. Mahdi Saleh said. About 90 minutes later, a car bomb exploded a few miles away as an Iraqi army patrol passed, killing two soldiers, Saleh said. Two soldiers and three civilians were wounded in the attacks. Al-Qaida in Iraq claimed responsibility for the attacks in a Web statement, but the authenticity of the posting could not be confirmed. Six civilians were also killed in the Tal Afar fighting and 22 were wounded, according to the city police chief, Brig. Gen. Najim Abdullah al-Jubouri. Some of the wounded were hospital workers, officials said.