Bajaur : A teenage suicide bomber targeted security personnel in a crowded market in the restive Bajaur tribal region of northwest Pakistan on Friday, killing 17 people and injuring 42 others, officials said.

The security personnel had gathered at a shop at the bazar in Khar, the main town of Bajaur Agency, after conducting a patrol when the teenage attacker approached them and detonated his suicide vest, witnesses told the media.

Four personnel of the Levies militia were among the 17 people killed, officials told the media. At least 42 injured people were taken to a nearby hospital, they said. Several injured persons were in a serious condition.

Soon after the blast, security forces cordoned off the market while authorities imposed curfew in Khar. Troops set up check posts and began checking people.

Footage on television showed a building that was reduced to a pile of bricks by the powerful explosion. People dug through the rubble with their hands to remove anyone who could be buried under the debris. Bloodstained currency notes, ID cards and shoes could be seen lying at the site of the blast.

Witnesses told the media that the suicide bomber was aged about 15 to 17 years. Officials said they had found the body parts of the attacker.

No group claimed responsibility for the attack though such incidents are usually blamed on the Pakistani Taliban. At least four persons were killed by a bomb blast in Bar Chamarkand area of Bajaur Agency yesterday.