More than a dozen Afghan police officers have been killed after they were mistakenly targeted by a US airstrike.
A spokesman for the local police said the officers were bombed as they mounted an operation against Taliban insurgents in Helmand province on Friday.
"In the strike, 16 Afghan policemen were killed including two commanders. Two other policemen were wounded," police spokesman Salam Afghan told AFP news agency.
The US has confirmed that it had carried out an airstrike in the area and offered its condolences to the families of those killed.
Hayatullah Hayat, the governor of Helamnd, has said the police are thought to have been out of uniforms at the time of the incident and may have been mistaken for Taliban fighters.
They were at a compound in Helmand's Gereshk district which they had recaptured from the militants when they were hit.
While much of Helmand province is under the control of Taliban, Afghan national security forces have been waging fierce battles to retake territory.
They are being supported by NATO and US troops which are stationed in Helmand to assist local security forces.