A roadside bomb exploded near a group of U.S. soldiers in northern Iraq on Wednesday, wounding three of them, the military said. Another six Iraqis were reported injured. The explosion occurred about 8 a.m. outside of Mosul, which is 225 miles northwest of Baghdad. Additional details were not immediately available, the military said. In recent months, such devices have become a weapon of choice among Iraqi insurgents. The bombs - usually made from mortar shells and explosives - are routinely placed along the roadsides and detonated as American convoys pass.