An Afghan soldier mistakenly opened fire on a US patrol in southern Afghanistan, killing two soldiers, an Afghan Defence Ministry official said Saturday, DPA reported.
The Afghan soldier fled after shooting the US soldiers Friday night near an Afghan army camp in Sangin, a dangerous district in Helmand province, planning official Mohammed Azim Mujahid said.
"Afghan and NATO forces are investigating, and a delegation has been sent to Sangin," he said.
The Taliban issued a statement Saturday saying an Afghan soldier shot and killed the troops at their base and then surrendered himself to the militants. They put the US death toll at three.
"The soldier didn't have any contact with the Taliban," Mujahid countered, adding that the soldier used the cover of darkness to escape. "It was only an accident."
In July, an Afghan soldier shot dead two US civilian trainers before being killed in northern Afghanistan.
Another soldier stationed in Helmand province killed three British troops in July.
Friday's attack took to 622 the number of foreign troops killed in the Afghan conflict so far this year, according to iCasualties.org, an independent website that tracks foreign troop fatalities in Afghanistan. It is the deadliest year for foreign forces since they deployed after the Taliban's ouster in 2001.