Lieutenant-colonel Mike Smith, the Isaf spokesman in the south of the country, said: "This is an indiscriminate use of a Taliban extremist bomb which has killed and injured both civilians and soldiers."

The attack came at the southern tip of Uruzgan province, near the border with Helmand and Kandahar, among the most violent areas in Afghanistan and the heart of the poppy-growing region.


Taliban fighters have stepped up the number of suicide attacks against the nearly 50,000 foreign troops in Afghanistan in 2007 after suffering heavy casualties in conventional attacks.

Also on Tuesday, the Taliban claimed responsibility for shooting down an Isaf helicopter.