Man in Afghan army uniform shoots dead Nato soldier
A Nato soldier in the eastern Afghan province of Kunar has been shot dead by a man in an Afghan army uniform, officials say.
Nato says the incident is under investigation.
There have been a growing number of cases where Afghan soldiers have killed Nato colleagues. At least 20 foreign troops have been killed in "rogue shootings" this year.
Observers say this has eroded morale among foreign forces.
Only Taliban bombs and attacks have killed more foreign troops in Afghanistan, correspondents say.
A Nato statement gave no further details about Friday's attack and did not specify the nationality of the dead soldier.
But local officials in eastern Afghanistan confirmed the incident took place in Kunar province.
"An Afghan army soldier turned his weapon against US soldiers inside an Afghan-US military base in Kunar province, killing one US soldier and injuring two others," provincial police chief Ewaz Mohammad Naziri told the AFP news agency.
Members of the Nato-led Isaf force are training their Afghan counterparts in preparation for a full handover of responsibility for security by 2014.
Revelations in February that US troops burned copies of the Koran at a base in Afghanistan - reportedly by accident - as well as the shooting of 16 Afghans by a US soldier in March have inflamed public opinion against the foreign forces.
"Isaf has officially recorded 15 green-on-blue incidents, which have resulted in 20 coalition deaths to date in 2012," an Isaf spokesman told the BBC.
That compares with 21 such attacks last year, which resulted in 35 coalition deaths.
"There is no indication that these incidents are linked or part of any larger co-ordinated effort," the spokesman said.