An Afghan official says at least eight people, including civilians and soldiers, were killed when a vehicle packed with explosives was remotely detonated in the country's south.

Omar Zwak, spokesman for the governor of Helmand province, says five civilians, two soldiers and a policeman were killed in Tuesday's attack in the Sangin district.

Nine others, including four civilians, four soldiers and a policeman, were wounded in the blast.

Helmand has been the scene of heavy fighting in a number of poppy-producing districts including Sangin since the army launched a major operation against Taliban strongholds last month.

No one claimed responsibility for Tuesday's attack. Taliban fighters are expected to step up attacks as the traditional spring fighting season approaches.