At least eight Afghans working with United States forces have been killed in a Nato air strike in north-western Afghanistan, the defence ministry in Kabul says.
Nato has confirmed an air strike was ordered and is investigating whether it was the cause of the deaths on Friday, the BBC reports.
It was launched as US and Afghan forces reportedly came under insurgent attack during search operations in Badghis province for two missing US soldiers.
Five Americans and 18 Afghans were also wounded on Friday.
The Afghan defence ministry said a base housing coalition troops and Afghan security forces was mistakenly hit.
Four Afghan soldiers, three police and another person believed to have been an interpreter were killed.
The Afghan deaths comes days after an Afghan policeman killed five British troops in Helmand province, who the soldiers had been training.