US fighter planes have bombed a suspected Taleban hideout in the same area of eastern Afghanistan where US servicemen are missing, officials say.
The US says that precision guided weapons were used
A senior Afghan official told the BBC 25 people had been killed in two air raids on a house in Chechal village.
US military spokesman Lt Col Jerry O'Hara told AP news agency: "We conducted an air strike on a target we deemed we had to hit immediately."
At least 39 people have been killed in three other clashes in Afghanistan.
More than 500 people, most of them suspected militants, are now estimated to have lost their lives in bloodshed in the south and east in the past three months.
Lt Col O'Hara said the air strike in the east was carried out with precision-guided weapons on a target that was "intelligence driven".
He said the target was an "enemy compound" in Kunar province.
A high-ranking Afghan security official in the province, speaking on condition of anonymity, told the BBC there had been two separate bombing runs on Chechal village.
Villagers who went to help those killed and injured in the first raid were hit by the second strike, he said.
The official said security forces had been sent to the area to find out who had been in the houses that were hit.
US officials say they have "no information" to confirm or deny the reports that civilians were killed.
There is rising US concern over the whereabouts of a team of US special forces on a reconnaissance mission who have been missing since Tuesday.
A helicopter which was sent to pick them up was shot down, killing 16 servicemen on board.
US forces hunting the missing ground team say they are using all available means, including unmanned surveillance aircraft and numerous ground troops.
But their efforts have been severely hampered by bad weather.
Violence has been escalating in Afghanistan ahead of parliamentary elections due in September.
More than 500 people have died in the past three months
On Saturday, the governor of central Uruzgan province, Jan Mohammad Khan, said 25 Taleban rebels and six Afghan soldiers had died in two clashes on Friday.
Taleban spokesman, Mullah Abdul Latif Hakimi, said six insurgents had died and 14 policemen were killed.
In a second clash in Kandahar on Saturday, the US military said Afghan and US troops had killed two militants who had attacked them with small arms fire.
In the third incident, in eastern Paktika province, two Afghan soldiers and four policemen were reported killed after their convoy, which included UN staff, hit a landmine.
The provincial police chief was among those wounded, Paktika's governor, Gulab Mangal, said.