A NATO airstrike mistakenly killed five Afghan soldiers, forcing Gen. David Petraeus to begin his tenure commanding the coalition effort there with an apology for the friendly fire incident. The few such incidents in Afghanistan, usually due to bad communication or darkness, have further driven a wedge between the American and Afghan militaries. The soldiers killed were readying for a raid in the south-central part of the country, in Ghazni province. NATO forces thought they were insurgents. The incident is under investigation. Separately, the U.S. announced three American deaths from an IED in the south.