Car bombs exploded among shoppers in downtown Baghdad on Saturday, killing at least eight people, police said, while a mortar attack on the U.S. government's representative office in central Iraq reportedly sparked a fire in part of the complex. At least 20 others were injured when a pair of bombs hidden beneath two cars detonated at 11:45 a.m. (0845 a.m.) at Hafidh al-Qadhi square, Lt. Ali Muhsin of the Rissafa police station, said, the Associated Press reported.