The soldier, identified Friday as US Army Staff Sergeant Robert Bales, had served three combat tours in Iraq, and was on his first deployment to Afghanistan.

Bales allegedly left his base in the southern province of Kandahar before sunrise Sunday, entered an Afghan village and opened fire, killing men, women and children. The incident has plunged US-Afghan relations into the deepest crisis since the 2001 US-led invasion.

The US military has not officially released the soldier's name, nor charged him with a crime yet.

Bales is expected to be held at Fort Leavenworth as army investigators seek to learn more about the tragic events. (AFP)