Coalition forces have carried out an air strike in the Herat region of western Afghanistan, killing 30 Taleban militants, the US military says.
A local Taleban commander was among those killed, it said.
Afghan government officials initially backed the claim but then appeared to dispute it, saying 91 civilians were killed, women and children among them.
The US military said it was confident no civilians had been killed in the air strike in Herat's Shindan district.
Casualty figures are often manipulated for propaganda in Afghanistan, BBC correspondent Alastair Leithead says.
The country's insecurity makes independent verification of any claims difficult, he says.
The US military said the air strike took place after a patrol of Afghan and coalition soldiers that had been aiming to arrest Mulla Sadiq, a Taleban commander, came under fire as it approached his compound.
"Insurgents engaged the soldiers from multiple points within the compound using small-arms and RPG (rocket-propelled grenade) fire," it said.
"The joint forces responded with small-arms fire and an air strike killing 30 militants."
Five militants were also arrested in the raid, the US military said.
In a statement soon afterwards, Afghan defence spokesman Gen Zaher Azimi gave a different assessment.
"Twenty-five Taleban were killed, including Sidiq and one other commander," he reportedly told AFP news agency.
But, he said, five civilians were also killed - three women and two children.
The Afghan interior ministry then issued a statement saying dozens of civilians had been killed in raid.
A provincial police chief said many women and children were among the dead.
According to separate reports from elders and local people, more than 50 people were killed and over a dozen houses destroyed.
In a separate incident in eastern Afghanistan, a bomb blast has killed a soldier from the US-led coalition.