BAGHDAD, Nov 20 (Reuters) - The U.S. military said on Tuesday its troops had killed 12 suspected al Qaeda fighters and found two shackled bodies in a makeshift detention facility during raids along the Tigris River north and south of Baghdad. In one operation near Samarra, 100 km (60 miles) north of Baghdad, U.S. troops called in air strikes after they came under fire while searching for leaders of the Sunni Islamist group in Iraq, the military said. The air strikes killed five militants. Another five were killed by ground troops when they entered a nearby building. "The ground force discovered an al Qaeda in Iraq detention facility which contained the bodies of two additional men bound in shackles and believed to have been executed," the U.S. military said in a statement. It said it appeared the men had been killed before U.S. troops arrived. It was the second such find announced by the U.S. military this week. Another suspected al Qaeda fighter was killed during raids in Mosul, 390 km (240 miles) north of Baghdad, and another was killed south of Baghdad, the U.S. military said. The operations took place on Sunday and Monday. Senior U.S. military leaders have said northern Iraq remains the most troublesome area after a security crackdown was launched in and around Baghdad in February. U.S. military and civilian casualties have dropped sharply in the past two months, partly as a result of 30,000 extra U.S. troops targeting al Qaeda fighters and Shi'ite militias. The troops became fully operational in mid-June. The military says attacks have dropped 55 percent since the troop "surge", a last-ditch attempt to avert sectarian civil war between majority Shi'ites and minority Sunni Arabs. More efficient Iraqi security forces and increasing use of U.S.-backed neighbourhood police units organised by mainly Sunni Arab tribal leaders have also been credited for falling violence. On Monday, the U.S. military said it had found an "execution site" and torture room during raids against al Qaeda along the Diyala River valley north of Baghdad from Nov. 6-10. The remains of five people were found in the execution site on Nov. 9, the military said in a separate statement. Eight suspected al Qaeda fighters were killed. (Reporting by Paul Tait; Editing by Janet Lawrence)
