A suicide bomber killed one policeman and two civilians in an attack on an Afghan police convoy in the southern province of Helmand on Monday, a Reuters witness said.

"The bomber detonated explosive attached to his body in the Lashkar Gah bazaar this morning and killed two civilians, including one child and one Afghan police," said Reuters reporter Abdul Qudoos at the scene of the attack.

Three policemen and five civilians were also wounded in the attack, a police official said.

Lashkar Gah is home to the headquarters of the British-led battle group in Helmand which has been involved in some of the heaviest fighting in Afghanistan in the last 18 months.

No foreign troops were wounded in the attack, a British army spokesman said.

There was no immediate claim of responsibility.

Taliban fighters have carried out more than 130 suicide bombs so far this year, killing more than 200 people in their campaign to oust the Afghan government and force foreign troops to leave the country.

PHOTO CAPTION

NATO troops in Kabul, Afghanistan [AFP]

Reuters