Kabul: An Afghan policeman opened fire at a training centre in Herat province and killed three Americans, a report said on Sunday.
CNN quoted a police official, who requested anonymity, as saying that the three killed were most probably trainers at the West Zone Police Training Centre. The official also revealed that the shooter was also killed.
Major Adam Wojack, a NATO spokesman, said the victims were civilian contractors working for the International Security Assistance Force. He however did not confirm their nationality.
Giving a different account of the incident, Wojack said that gunman donned an Afghan Army uniform.
More information will be released on Monday, he said.
(With Agency inputs)