At least 17 people, including 12 Afghan army soldiers, were killed Thursday in a helicopter crash in southern Afghanistan, the worst such incident suffered by military forces since December.

At least 17 people, including 12 Afghan army soldiers, were killed Thursday in a helicopter crash in southern Afghanistan, the worst such incident suffered by military forces since December.

The military helicopter went down due to technical fault in Shinkay, a district relatively free of insurgent activity in the otherwise volatile province of Zabul.

"Five crew and 12 soldiers were killed when the helicopter crashed in Shinkay district of Zabul province due to technical issues," a provincial police official said.

Shinkay district chief Mohammad Qasim Khan confirmed the death toll, with an army commander saying an official delegation has been dispatched to the area to investigate the crash.

Aircraft crashes have been a regular risk for Afghan and foreign coalition forces, with troops relying heavily on air transport to traverse Afghanistan's rugged terrain.

In 2001, Taliban terrorist operatives brought down NATO helicopters, notably a US Chinook, which killed 30 Americans, but such incidents have been rare.

In April last year five British troops died when their helicopter crashed in Kandahar province in what London's Ministry of Defense said at the time appeared to be a "tragic accident".