A bomb planted on a motorbike killed six people and wounded another 15 on Friday in a crowded market in troubled southwestern province Baluchistan, police said.

The bomb, detonated by remote control, exploded near a bus station in the remote town of Dera Allah Yar, around 170 miles (270 kilometres) southeast of Quetta, the provincial capital.

"At least six people have been killed and more than 15 injured. The bomb was planted on a motorcycle," police official Qamar Ul Hasan told AFP.

Hasan said the target of the attack was yet not clear.

"The bomb also badly damaged around five to six shops and destroyed some motorbikes and other vehicles," he said.

There was no immediate claim of responsibility.

Zulfiqar Ali, a second police official, confirmed the attack and warned that the death toll could rise further.

"All those killed were civilians," Ali told AFP. Rescue teams arrived at the scene and the injured people were shifted to near-by hospitals