Gunmen killed a senior leader of a U.S.-allied group and six of his guards in an ambush south of Baghdad, a group member said Tuesday. Roadside bombings also killed another person and wounded a dozen Tuesday, in a second consecutive day of bombings in the capital, the Associated Press reported. Unknown gunmen attacked the convoy of Sheikh Ibrahim al-Karbouli in Youssifiyah on Monday, said the group member. The Sheikh was a senior leader of the awakening council in the town.