Taliban guerrillas have captured a strategic district from the Afghan government after days of clashes in eastern Nuristan province, officials said on Sunday. Separately, the Afghan government said it was checking reports by locals saying some 40 Afghan civilians were killed in a raid by foreign forces in Sangin district of southern Helmand province on Friday, Reuters reported. In Nuristan's Barg-e Matal, dozens of Taliban fighters and up to six Afghan police were killed during days of clashes before the district fell to the Taliban overnight. Barg-e Matal is important for the government and militants because of its location and has regularly changed hands.