Afghan provincial officials in southern Helmand province revised the death toll for a reported bomb blast the previous day, saying five and not 21 civilians were killed, while in the same region five farmers were killed Thursday in a US airstrike, according to dpa. Meanwhile, the North Atlantic Treaty Organization said Thursday that a US soldier, serving under the banner of the alliance forces, was killed fighting the Taliban in western Afghanistan, while five police were killed by a roadside bomb in southern Helmand province. A bomb believed to have been planted by Taliban insurgents was set off by a passing tractor in Darwaishan area of Garmsir in the southern province of Helmand on Wednesday, killing five civilians, Assadullah Sherzad, the provincial police chief said, correcting his earlier figure of 21, according to dpa.