A car bomb detonated in the center of a town south of Baghdad on Thursday killing 20 and wounding 35, an Iraqi army officer said. Capt. Ibrahim Abdeallah said the suicide bomber was targeting US military vehicles parked near the hospital in Mahmoudiya, about 30 kilometers (20 miles) south of Baghdad. There was no immediate information about US casualties. Also Thursday, two US soldiers were killed by gunfire during combat operations in southwest Baghdad, the US military said. The soldiers were assigned to Task Force Baghdad, the statement said, but no further details were released. The name was withheld pending notification of kin.