A suicide bomb blast killed at least 13 people in Pakistan Thursday, the second explosion in two days.

Maulana Fazlur Rehman

A suicide bomb blast targeting an Islamic party chief killed at least 13 people in Pakistan Thursday, officials said -- the second attack against him and his supporters in two days.

The bombing took place in the northwestern town of Charsadda, close to the convoy of Maulana Fazlur Rehman, leader of the Jamiat Ulema-e-Islam (JUI-F) party.

"At least 13 people were martyred including four police officials and 42 others were wounded in the suicide bombing," senior administration official Ajmal Khan said.

"The bomber was on foot and he jumped on the main road in front of the police vehicle and detonated his explosive when the convoy of Maulana Fazlur Rehman was coming," Khan added.

Rehman and his companions were unharmed, but two security guards travelling in the vehicle in front were wounded. Their vehicle was damaged in the bomb blast.

Reprts said the bombing left seven shops and three vehicles wrecked, with walls scarred by blood spots and pellet marks.

Rehman's party walked out of the national ruling coalition on December 14 after Prime Minister Yousuf Raza Gilani sacked one of its three cabinet ministers over a war of words with religious affairs minister Hamid Saeed Kazmi, who was also fired.

Pakistani PM_Yousuf Raza Gilani

The spat related to a corruption scandal over accommodation for tens of thousands of Pakistani pilgrims that reportedly implicated Kazmi's ministry.

Rehman has demanded Gilani's resignation, and has also led rallies that forced the government to abandon possible changes in the country's blasphemy law.

"Terrorists have no religion. If they can bomb mosques, they can attack religious and political leaders also," provincial information minister Mian Iftikhar Hussain said.

"Every politician is under threat here," he added, referring to frequent militant attacks on government and security officials and places of worship in the northwestern province of Khyber Pakhtunkhawa, which borders Afghanistan.

More than 4,000 people have died in suicide and bomb attacks throughout Pakistan since government forces launched an offensive against militants in a mosque in Islamabad in 2007.

Taliban and Al-Qaeda-linked militants launch almost daily attacks across northwest Pakistan and the tribal belt that Washington has branded the most dangerous place on Earth