By Charles Haviland

BBC News, Kabul



Villagers say they came under air attack for several hours

Coalition and Nato-led forces, in co-operation with Afghan troops, launched the strikes against Taleban insurgents on Friday.

Local officials say they believe tens of civilians died but there has been no independent confirmation of this.

President Hamid Karzai recently accused foreign troops of acting "recklessly".

The coalition said the latest incident had been sparked when its forces, working with the Afghan national army to clear a river valley, came under heavy insurgent fire, including the use of rocket-propelled grenades.

It said its forces had identified several rebel positions, returned fire and then called in air strikes by the coalition and the Nato-led Isaf, which destroyed all the rebel positions.

A coalition spokesman said that later the remains of people who appeared to be civilians were found and that these bodies were in the places previously defined as firing positions.

Saying he was deeply saddened by any civilian deaths, the spokesman said insurgents were continuing to put women and children in harm's way.

'Rescue'

Earlier, Helmand's police chief said the foreign forces had not consulted their Afghan counterparts before launching the air strikes.

But a Nato spokesman denied this, saying the air power was used to help rescue the Afghan army.

The mayor of the nearby town of Gereshk told the BBC there were reports of tens of civilian deaths.

Local people who telephoned the BBC said that as many as 50 to 80 civilians had been killed.

They said "foreign forces" had bombed their area for two to three hours late on Friday.

A week ago, after the death of some 25 civilians in the same district, President Karzai accused foreign forces of acting recklessly and ordered them to co-ordinate better with his government.