At least 13 Afghan civilians have been killed in a Nato air strike near Kabul, a provincial official says.
Thirteen others were injured, the head of Wardak provincial council said.
The Nato-led International Security Assistance Force (Isaf) confirmed it had bombed an "insurgent position" but said it had no evidence civilians died.
Civilian deaths have risen as conflict in Afghanistan has worsened. It is often difficult to establish if claims of civilian casualties are accurate.
The BBC's Alastair Leithead in Kabul says the areas where civilian deaths are reported are often remote and hostile, and the dead are buried within 24 hours.
He says avoiding the death of civilians in counter-insurgency operations is vital for the success of the Nato mission in Afghanistan.
President Hamid Karzai has repeatedly called on foreign forces to exercise more care in the battle with the Taleban and their allies.
Wardak provincial council head Haji Hazrat Janan said he had visited the site of the bombing raid in Jalrez district, bordering Kabul province.
President Karzai says foreign forces must do better
Local people had told him 11 members of one family were among those killed, he said. Two others had also died and 13 were injured.
One man he spoke to said his wife and his daughter-in-law were killed in the attack and that the body of a child had also been recovered from the rubble.
"The only survivor from the family is a man who is hospitalised and can't speak," Haji Janan said, Reuters news agency reports.
An Isaf spokesman confirmed there had been an air strike in the area at around 0900 on Monday morning but said it was targeting a known insurgent position.
He said there was evidence that an ambush of Isaf troops was being set up and so a bombing raid was called in, adding that Nato had not received any reports of civilian casualties but troops on the ground were investigating further.
An Afghan national army local commander said 20 Taleban were killed in the attack from the air and that only three civilians were injured.
Violence has soared in Afghanistan, with more than 3,000 people killed this year as Afghan and foreign forces battle Taleban fighters.
Most of those killed are insurgents, as well as many Afghan security personnel and foreign soldiers.
Several hundred civilians have also been killed - exact numbers are impossible to establish. Western forces dispute estimates given by aid workers and Afghan officials.
The worst of the fighting has been in the south and the east, but Wardak province has seen a recent rise in violent incidents.