A member of a fact-finding mission said on Friday that 13 civilians, most of them women and children, were killed in the US airstrike in Parwan Province on Wednesday. Initial reports had put the death toll at 8.
In a press conference in Kabul, the Afghan official said most of the victims were women and children.
The fact-finding mission began work after President Hamid Karzai ordered an investigation into the deadly attack.
A large number of civilians have been killed or injured at the hands of US-led foreign forces — most of them in nighttime raids and airstrikes. The casualty rate has risen over the past few months, even though the Afghan government had asked foreign forces to make every effort to avoid killing civilians.
An escalation in the US-led strikes on Afghanistan’s civilian areas has angered both the public and the government.
Afghans have held numerous protest rallies countrywide to condemn such attacks.
Afghan government officials — including President Karzai himself — have also frequently condemned the killings of civilians by foreign forces.
The latest development comes as the US and Afghanistan are still at loggerheads over a bilateral security deal. Washington has been mounting pressure on Kabul to sign the deal that would allow several thousands of US troops to stay in Afghanistan beyond 2014.
Afghan political figures have heaped scorn on the US-led forces for committing unforgivable crimes against Afghan women and children since invading the country in 2001.