The US military on Sunday reported three American troops killed, including a US airman in a roadside bombing in southern Iraq. The 586th Air Expeditionary Group airman was killed Sunday when the explosion struck convoy operations in southern Iraq, a statement said. An airman also was wounded in the attack but was listed in good condition and was expected to return to duty, it said. The attack occurred about 3 a.m., Air Force Capt. Shilo Weir said. A Multi-National Division - Baghdad soldier also was killed and another wounded Sunday during combat operations in a southern section of Baghdad, the military said separately. Another Multi-National Division - North soldier died of wounds as a result of injuries sustained from small-arms fire while conducting operations in Diyala Province on Saturday, a statement said, adding that one soldier also wounded in that attack.