The civilians were killed when US planes pounded a suspected militant hideout in rebel-infested Kunar province late Friday amid the search for a small team of US special forces soldiers, the governor said.

One team member was rescued Saturday but three remain unaccounted for, the television network CNN said. The US squad has been missing since June 28 when rebels downed a helicopter sent to extract them, killing all 16 on board.

"Coalition forces deeply regret the loss of innocent lives and are investigating the incident to prevent future occurrences," a US military statement said, without specifying the number of civilian deaths.

"Seventeen civilians died in the US bombing" of Chichal village in Kunar, provincial governor Assadullah Wafa told AFP. "There are a number of children and women among the victims but I don't have the exact figure right now."

Military helicopters and other aircraft were still patrolling the area but there had been no more bombing, Wafa added.

American-led forces have mistakenly killed scores of Afghan civilians since engineering the fall of the Taliban regime in late 2001, including 48 who died when a wedding party came under attack three years ago.

The US statement said American forces struck a "terrorist compound in Kunar province with precision-guided munitions that resulted in the deaths of an unknown number of enemy terrorists and non-combatants.

"The targeted compound was a known operating base for terrorist attacks in Kunar province as well as a base for a medium-level terrorist leader. Battle damage assessment is currently ongoing," the statement said.

It said that US forces followed strict rules to avoid civilian deaths but added that "when enemy forces move their families into the locations where they conduct terrorist operations, they put these innocent civilians at risk."

The ousted Taliban regime, which claimed responsibility for shooting down the MH-47 Chinook helicopter last week, said Saturday that US bombing had killed 25 civilians including children.

Afghan President Hamid Karzai voiced concern in May about civilian deaths in US-led operations, and US President George W. Bush's special envoy to Afghanistan Zalmay Khalilzad said he regretted the loss of civilian lives.

US forces continued the major anti-insurgent offensive in which the missing servicemen had been taking part, although the military denied reports that there had been further bombing since Friday.

"There's a search and recovery mission, along with ongoing operations," US spokesman Lieutenant Colonel Jerry O'Hara said. "There is a lot of air activity ongoing, but there have been no air strikes over the last three days."

The soldier rescued on Saturday had evaded Taliban rebels throughout the past week, CNN and the BBC reported Sunday.

Taliban spokesman Abdul Latif Hakimi said Sunday the rebels had captured a US soldier and would release footage of seven "American spies" who had been killed, along with film of the captured soldier.

Attacks blamed on the Taliban have risen in recent weeks ahead of September 18 parliamentary elections. The downing of the helicopter was the biggest loss of life suffered by US forces in Afghanistan.

Media organisations said Monday that four Afghan journalists covering the ongoing US-led operation in Kunar have been detained by local security agencies. Intelligence officials would not comment.

The detained journalists include two reporters from Prague-based Radio Free Europe and another pair who worked for a western news agency. Their company in Kabul requested that their identities not be released.

The Brussels-based International Federation of Journalists said it was "deeply concerned" by reports that the journalists had begun a hunger strike in custody.