A Nato airstrike has killed four Afghan soldiers who the coalition said were mistaken for militants in the country's south, a spokesman for the Afghan defence ministry said on Thrusday.
The soldiers had left their base in Helmand's Musa Qala district last night when they came under fire from Nato planes, said Gen Mohammad Zahir Azimi.
Nato told the Afghan government that the coalition thought the men were militants, he said.
A spokesman for Nato forces, Capt Ciro Parisi of the Italian Army, said a team has been sent to investigate the incident. He would not confirm any of the details of Azimi's account, citing the ongoing investigation.
There have been other incidents this year in which Nato troops mistakenly killed Afghan forces.
In August, three Afghan policemen were killed in northern Jowzjan province in an airstrike aimed at insurgents who were attacking them. In July, In July, a botched Nato airstrike killed six Afghan soldiers in Ghazni province in the east.
The coalition said the Afghan army unit gave the wrong location to international forces.