From the AP,

KARACHI, Pakistan (AP) - Police stepped up security patrols Monday while Islamic hard-liners called for a nationwide strike after a leading pro-Taliban cleric was gunned down, touching off massive rioting by his followers.

The situation was tense but there was no immediate outbreak of violence following a day of unrest that saw police fire tear gas and warning shots to disperse rioters who set fire to banks, shops, a police station and a KFC fast-food restaurant.

Police formed a special task force to investigate the slaying of Nazamuddin Shamzai, a cleric in his 70s who had been a strong supporter of the former Taliban regime in neighboring Afghanistan and had met al-Qaida chief Osama bin Laden.

The cleric, from the Sunni branch of Islam, had a large following in Pakistan. The United Action Forum, a coalition of six fundamentalist parties, called for a "complete nationwide strike" Friday to protest his slaying and to pressure police to arrest the attackers.

"We will not sit silent. We will protest against the brutal murder of a great religious personality," Maulana Fazur Rahman, a senior leader of the forum, told reporters as he visited Shamzai's home to express condolences.

"We will be forced to take other steps if the killers of Nizamuddin Shamzai are not arrested," Maulana said, without elaborating.

Hundreds of policemen and paramilitary rangers patrolled neighborhoods wracked by unrest Sunday. But residents remained indoors or went about their business against a backdrop of burned-out shopfronts and the carcasses of torched cars.

The identities of the killers are unknown and no one has claimed responsibility. Police have issued a sketch of one suspect.

Witnesses said the assassination team included as many as six gunmen riding in two cars and a motorcycle. They sprayed Shamzai's car with bullets Sunday morning, killing him and wounding one of his sons, a nephew, a driver and a police bodyguard.

The shooting was condemned Sunday by Prime Minister Zafarullah Khan Jamali as a "dastardly act of terrorism."

Religious violence is common in Karachi, Pakistan's biggest city, and is usually blamed on outlawed extremist groups from the Sunni majority and Shiite minority. Places of worship of both branches of Islam are common targets, as are those of minority Christians.

The slaying of Shamzai, who ran one of Karachi's largest religious schools, came three weeks after a suicide bomber killed 22 worshippers at a Shiite mosque and four days after two car bombings near the U.S. Consul's residence killed one person and injured 40.