A bomb went off outside the home of a provincial minister in a suburb of Peshawar in northwest Pakistan on Sunday, injuring at least four persons, including policemen, officials said.

The blast occurred outside the residence of Khyber-Pakhtunkhwa Agriculture Minister Arbab Ayub Jan, who belongs to the ruling Awami National Party.

It could not immediately be ascertained if the minister was at home at the time of the attack.

Several policemen posted at a check post outside the residence were among the four persons injured in the blast, police officials were quoted as saying by TV news channels.

The nature of the blast could not immediately be ascertained.

Some reports said the attack was carried out with a remote controlled explosive device.

No group claimed responsibility for the attack.

Scores of ANP leaders and workers have been killed in attacks by the banned Pakistani Taliban over the past few years.

The attack came six days after US special forces gunned down al Qaeda leader Osama bin Laden in the garrison city of Abbottabad, also in Khyber-Pakhtunkhwa province.