A US air strike in eastern Afghanistan on Sunday killed 47 civilians, 39 of them women and children, an Afghan government investigating team says.
Reports at the time said that 20 people were killed in the airstrike in Nangarhar province. The US military said they were militants.
But local people said the dead were wedding party guests.
Correspondents say the issue of civilian casualties is hugely sensitive in Afghanistan.President Hamid Karzai has said that no civilian casualty is acceptable.
Demand for trial
Mr Karzai set up a nine-man commission to look into Sunday’s incident.
The commission is headed by Senate deputy speaker, Burhanullah Shinwari whose constituency is in Nangarhar province. He told the BBC: ”Our investigation found out that 47 civilians (were killed) by the American bombing and nine others injured.
“There are 39 women and children” among those killed, he said. The eight other people who died were “between the ages of 14 and 18″.
A spokeswoman for the US coalition, Lt Rumi Nielson-Green told the AFP news agency that the force was also investigating the incident and regretted any loss of civilian life. “We never target non-combatants. We do go to great length to avoid civilian casualties,” she said.
At the time the US said that those killed were militants involved in previous mortar attacks on a Nato base.
The incident happened in the remote district of Deh Bala, close to the Afghan border.
Mirwais Yasini, deputy speaker for the lower house of parliament, also has his constituency in Nangarhar. ”We are very sad about the killings in Deh Bala. People should be compensated,” he told the BBC.
“These operations widen the gap between the people and the government.”
He said that those who passed on intelligence to the US military ahead of the air strike should be tried, "as well as those who carried out the bombing".
Mr Yasini demanded that "all operations should be conducted in full co-operation with our security forces in the future".
Correspondents say most civilian deaths in Afghanistan are caused by Taleban fighters and other militants opposed to President Karzai and US and Nato-led forces. On Monday a suicide attack on the Indian embassy in Kabul killed 41 people, most of them civilians.
However, foreign troops have also often killed civilians, leading to an erosion of support for their presence in Afghanistan.
Last year a US army spokesman said he was "deeply ashamed" after US marines killed 19 civilians near Jalalabad in Nangarhar province.
Only a few months earlier, a Nato spokesman said that civilian casualties were the main issue for the Nato-led force to resolve.
"I believe the single thing that we have done wrong and we are striving extremely hard to improve on is killing innocent civilians," Brig Richard Nugee said.
President Karzai has been scathing in his criticism over the deaths of Afghan civilians, even summoning foreign commanders in May, 2007 to tell them "that the patience of the Afghan people is wearing thin with the continued killing of innocent civilians".
Two days ago, the Red Cross said that at least 250 Afghan civilians had been killed or wounded in insurgent attacks or military action in the previous six days. It called on all parties to the conflict to avoid civilian casualties.