KABUL - At least three dozen Afghan police and civilians have been killed in two separate airstrikes by the NATO-led force in Afghanistan, Afghan officials said Sunday. A NATO military spokesman in Kabul said the coalition was aware of both incidents and had begun investigations. The reported deaths of 14 civilians in an area of southern Helmand on Saturday, and 22 police plus other civilians in northeastern Nurestan on Wednesday will likely add to the long-running tension between Kabul and its Western allies about civilian casualties caused by the foreign forces.