NATO says an Afghan soldier was killed as he tried to gun down a group of international troops in the country's east.
A NATO spokesman said the attack happened outside a "coordination center" for Afghan and international forces in Laghman Province.
German Lieutenant Colonel Hagen Messer said no NATO troops were killed in the incident.
Messer declined to give more details, saying only that NATO and Afghan forces need to investigate the attack.
He also declined to say if anyone was wounded.
The incident is the latest in a growing number of the "green-on-blue" attacks in which Afghan soldiers or police have turned on their international colleagues.
According to an AFP tally, some 30 people have died in 22 such incidents.
Based on reporting by AFP and AP