Two coalition service members died Saturday morning in southern Afghanistan in an apparent insider attack in which two men wearing Afghan security forces uniforms opened fire at an Afghan compound, coalition officials said.

Coalition troops returned fired and killed the shooters, according to a news release. Few additional details were immediately available about the shooting, but the soldiers killed were Romanian, according to the Foreign Ministry in Bucharest and a defense official in Kabul. The shooting occurred in Kandahar province, the official said.

“Afghan and Resolute Support officials are conducting an investigation into the incident and further information will be released as available and appropriate,” the coalition said in a statement. “We continue to train, advise and assist the [Afghan forces], and do not view this incident as representative of the positive relationship between our forces.”

Casualties in the war in Afghanistan have plummeted since 2014, as the U.S.-led military coalition pulled back almost entirely onto a few large installations.

The last coalition service member killed was Army Staff Sgt. Matthew Q. McClintock, a Green Beret, who was hit with enemy fire in Helmand province’s Marja district on Jan. 5.