Five NATO troops and an Afghan soldier were killed in a friendly-fire airstrike in southern Afghanistan, dpa cited Afghan officials and Taliban as saying Tuesday. The NATO-led international military alliance said the soldiers were killed Monday in the southern part of the country, but did not give details on the nationalities of the deceased soldiers or the exact location of the incident. Afghan police said that NATO aircraft bombed the soldiers. "They were returning from an operation launched in Gazak area of Arghandab district last night and faced a Taliban ambush," said Ghulam Sakhi Roghlewanay, the Zabul provincial police chief. "They asked for an air support, but the aircraft mistakenly bombed their own soldiers in which five foreign and one Afghan soldier were killed."