Gunmen wearing Afghan security forces’ uniforms opened fire on a vehicle at a base in southern Afghanistan on Wednesday, killing two international service members and two Afghan soldiers, officials said.
International troops returned fire and killed both gunmen, according to a statement by U.S.-led coalition forces.
The nationalities of the two foreign troops were not immediately disclosed. Coalition officials said they were reviewing the incident, which took place early Wednesday in the southern province of Helmand.
No group immediately claimed responsibility.
It was at least the third so-called insider attack on foreign forces in Afghanistan this year.