Afghan officials said an airstrike has killed 17 policemen by mistake during a battle with the Taliban just outside the provincial capital of Lashkar Gah in the country's southern Helmand province.
Attaullah Afghan, head of the provincial council, said the airstrike took place on Thursday as Afghan police were fighting the Taliban near the city.
Fourteen policemen were also wounded in the strike, he added, according to Al Jazeera.
It wasn't immediately clear who carried out the airstrike.
Spokesperson for the provincial governor said the strike was carried out by NATO Resolute Support force in the Nahr-e Seraj area of the Helmand-Kandahar highway.
There was no immediate response to a query to the US military in Kabul. American forces regularly back Afghan troops when asked to.
Helmand's governor, Mohammad Yasin, says the airstrike is being investigated. A Taliban statement claimed US forces were behind it.