Six U.S. service members were killed Tuesday when their helicopter crashed in Southern Afghanistan.
A U.S. defense official told Stars and Stripes that while the International Security Assistance Force has not released the names or nationalities of those killed, all six who lost their lives were Americans.
There was one survivor of the crash, according to Reuters, who suffered injuries in the accident.
NBC News has identified the aircraft that crashed as a Sikorsky UH-60 'Black Hawk' helicopter.
ISAF reports there was no known enemy activity in the area when the Black Hawk went down.
An investigation into what caused the crash is underway.
