Looks like Obama spoke too soon.

(CNN) — A gunman in an Afghan National Army uniform and another man shot and killed two service members with the NATO-led International Security Assistance Force in southern Afghanistan on Thursday, authorities said.

The two service members were American, an Afghan official said. The NATO-led force did not immediately specify the service members’ nationality.

It was the latest of several incidents in which someone in an Afghan military uniform killed Western troops.The shooting happened in a combat outpost in southern Afghanistan.

It follows a shooting that killed two U.S. military officers recently inside the Afghan Interior Ministry, which was thought to be highly secure. That incident prompted the U.S. to withdraw troops from several Afghan government buildings.