A man in civilian clothing opened fire on a base shared with Afghan forces, killing three NATO troops, a spokesman for the International Security Assistance Force said Saturday.
The shooting occurred late Friday in Afghanistan's volatile Helmand province, the same region where three American soldiers were killed hours earlier by a man in an Afghan military uniform, officials said.
Afghan and ISAF officials offered conflicting accounts over the latest shooting in Garmsir District, where U.S. Marines have been working with Afghan forces at a joint outpost.
An Afghan official said a local police officer opened fire, killing three Marines, while ISAF said the gunman was wearing civilian clothes.
The international coalition did not release the nationalities of the troops or details about the shooting or the location. The gunman was detained by troops shortly after the shooting Friday night, said Maj. Martyn Crighton of the ISAF Joint Command.
Haji Mohammad Khan, the deputy district chief, said a policeman opened fire on the Marines at the outpost located inside the Garmsir police compound.
But Crighton said the shooter was an Afghan civilian working on an installation shared by Afghan and NATO forces. He would not say whether the shooting occurred at the compound in Garmsir.
Brig. Gen. Gunter Katz, an ISAF spokesman, who also described the man as a civilian, said he had been detained after the attack.
It was the second Friday shooting targeting NATO troops in Afghanistan.
Three U.S. soldiers were killed when a man in an Afghan military uniform opened fire in the Helmand province, the latest in a series of assaults against NATO troops by Afghans wearing security force uniforms.