A roadside bombing struck a U.S. patrol northwest of Baghdad on Saturday, killing three American soldiers and two Iraqi civilians, the military said. The deaths raised the toll of American troops who have died since the war started five years ago to at least 3,996, according to a report of the Associated Press. Two of the Multi-National Division _ Baghdad soldiers were killed when the bomb struck their vehicle during a patrol, according to a statement. The third died later of wounds suffered in the attack, the military said.