An air attack has killed at least eight policemen by mistake during a battle with the Taliban outside the provincial capital of Lashkar Gah in

Afghanistan’s southern Helmand province, the United States military and Afghan officials said.

Colonel Dave Butler, Spokesman for US Forces Afghanistan, said Afghan security forces had called for US air support during a firefight late Thursday in Lashkar Gah, in southern province of Helmand.

The two parties had supposedly “deconflicted” their forces -- a military term for making sure neither side had troops in the attack zone.

The Afghan forces “confirmed the areas were clear of friendly forces”, Butler said.

"Unfortunately, they were not and a tragic accident resulted. Afghan security forces as well as Taliban fighters were killed in the strikes,” he said.

At least eight policemen were killed in the attack in the Nahr-e-Seraj area of the Helmand-Kandahar highway, said Omar Zwak, the provincial governor's spokesman. He said a dozen other police were wounded.

Interior Ministry spokesman Nasrat Rahimi on Facebook confirmed the death toll and said 11 police had been wounded.

Attaullah Afghan, the head of the provincial council, said the attack took place on Thursday while Afghan police were fighting the Taliban near the city. (Aljazeera)