The air strike late on Tuesday night hit houses in a village in the Sangin district on Helmand province, where Western forces have been hunting Taliban militants in recent weeks, Helmand governor Assadullah Wafa told Reuters.
"Last night, NATO forces carried out an operation in Sangin and as a result of its bombing, 21 civilians, including women and children and men, have been killed," he said.
Wafa said he had no report of casualties among the Taliban.
Helmand is a Taliban stronghold and the key drug-producing region of Afghanistan, the world's leading producer of opium.
NATO said it was not involved in an operation in the area but a soldier serving with U.S.-led coalition troops was killed in Sangin on Tuesday night.
A U.S. military spokesman said he had heard reports about civilians killed in this clash but his information was that the only other people killed were militants.
The incident in Helmand would bring to nearly 90 the number of civilian deaths at the hands of Western troops that have been reported in the past two weeks by Afghan officials.
Separately, four civilians were killed on Wednesday when a suspected suicide bomber apparently exploded his charge prematurely in the southeastern province of Paktika, officials said.
The Taliban have stepped up attacks in recent weeks, with both sides in the conflict looking for a decisive advantage this year, although rising civilian casualties have prompted renewed calls from Afghan politicians for peace talks with insurgents.
(additional reporting by Ismail Sameem and Elyas Wahdat)
- Reuters - Thomson Reuters Foundation
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