KABUL (Reuters) - The Nato-led force in Afghanistan believes civilians were killed and injured in an airstrike in northern Afghanistan called in by German troops, the force said in a statement on Tuesday. In previous statements, the force has said it believed civilians were harmed, but had not spelled out clearly whether they were killed. Subsequent review has led Isaf to believe that along with insurgents, civilians also were killed and injured in the strike, it said.