A suspected suicide bombing in Pakistan’s remote Bajaur tribal district in the northwest has killed at least 20 people and wounded at least 45, according to reports.

The blast, which apparently targeted security forces near a market in the village of Tehsil Khar, killed four or five tribal policemen, but also many civilians and bystanders.

BBC reported that the alleged bomber travelled on foot and carried an explosive in his vest which detonated when he arrived at a police checkpoint.

The Pakistan Tribune newspaper reported that the bomber appeared to be between the age of 14 and 18, according to eyewitnesses

Maulvi Faqir, leader of Tehrik-i-Taliban Pakistan (TTP) --- the local Pakistan Taliban -- claimed responsibility for the attack, although local officials have not confirmed that assertion. Faqir alleged that he was seeking revenge on a commander who had killed some of his compatriots last year.

A spokesman for TTP, Ehsanullah Ehsan, told Reuters: “We carried out the attack today. We are very happy today that we have achieved our target.”

Bajaur, which is near the Afghanistan border, has frequently witnessed fighting between Taliban militants and Pakistani soldiers.

Police have imposed a strict curfew in the area, which they have long claimed was secure anyway.

TTP is not directly affiliated with the Afghan Taliban and is dedicated to overthrowing the Pakistani state. TTP has been blamed for a wide variety of attacks on Pakistani institutions and government officials, including the December 2007 assassination of former Prime Minister Benazir Bhutto.