Five of the wounded were American soldiers, a spokesman for NATO's International Security Assistance Force (ISAF), told AFP.

ISAF spokesman Lieutenant Colonel Todd Vician, of the U.S. Air Force, told AFP: “We have nothing to confirm friendly fire.”

“No ISAF members were killed,” he said, confirming the injured ISAF soldiers were Americans.

Investigations into Friday's incident, believed to have happened in Badghis province, were ongoing and no further details were available, he said.

Local police in Badghis province said a party looking for the two missing soldiers clashed with Taliban and that alliance aircraft were called in to provide support.