A Nato helicopter called in to support Afghan police at a highway checkpoint opened fire and mistakenly killed five Afghan officers, officials have said.
The killings happened on Wednesday night in eastern Nangarhar province, about 75 miles from the capital, Kabul. Afghan policemen inspected what remained of the checkpoint.
Ahmad Zia Abdulzai, a spokesman for the provincial governor, said officers manning the checkpoint on Wednesday came under fire and called for air support from Nato troops.
The exact sequence of events is unclear, but Captain Malloy Ebony, a spokeswoman for the US-led International Security Assistance Force, said the Nato helicopter opened fire on the Afghan officers, killing five.