Hundreds of Islamic seminary students went on a rampage Tuesday at the funeral of an assassinated hardline Sunni Muslim (searchpolitician, setting fire to a Shiite Muslim shrine and a movie theater, smashing shop windows and chanting anti-Shiite slogans.

The violence at the funeral for Maulana Azam Tariq, the leader of the banned Sipah-e-Sahaba (searchextremist group and a member of Parliament, raised fears that his assassination could spark a new wave of sectarian killing in a country that has seen far too much of it in recent years.

Tariq was gunned down Monday afternoon along with three bodyguards and a driver as they drove near a toll plaza on Islamabad's southwestern outskirts.

On Tuesday, thousands flooded a main traffic intersection in front of the Parliament building for the funeral.

"Shiites are infidels!" many in the crowd chanted, as hundreds of heavily-armed police looked on.

"Shiites are involved in the killing of Maulana Azam Tariq," said Sheikh Hakim Ali, a supporter of Sipah-e-Sahaba. "The martyrdom of Azam Tariq is a matter of pride for us. We will continue his mission."

After a funeral prayer, the Islamic seminary students ran toward a nearby business district, using sticks to smash shop windows.

One of Islamabad's only movie theaters was set ablaze during the riot, and rescuers pulled out an unconscious boy from the building. It was not known whether he had any serious injuries.

Later, rioters set ablaze the Sakhi Mahmoood shrine -- a Shiite (search) shrine that is also popular with many Sunnis. Caretaker Gauhar Ali said everything inside the tomb was burned down.

Police used batons to disperse the crowd.

An ambulance was to move Tariq's body for burial to Jhang, a city about 180 miles southwest of Islamabad which has been the center of Tariq's sectarian political movement.

By midmorning, about 4,000 people had gathered waiting for the body to arrive. A funeral prayer was scheduled to be held at the city's sports stadium. Tariq is to be buried inside a complex that once served as the headquarters of Sipah-e-Sahaba.

Many in the crowd chanted slogans against Shiites and against President Gen. Pervez Musharraf, calling the Pakistani leader a "dog."

Most schools and shops in the city were closed and hundreds of policemen, many riding trucks mounted with machine guns, patrolled the streets.

Elsewhere in Pakistan, security was also tight.

Tariq was detained by Pakistan at the start of the U.S.-led military operation in Afghanistan to prevent him from leading pro-Taliban rallies. His group was later banned as President Gen. Pervez Musharraf sought to purge the country of extremism and terrorism.

He won a seat in Parliament from behind bars in October 2002, and was released shortly afterward when a court in the eastern city of Lahore ruled the government had not produced enough evidence to hold him.

Although Tariq denied supporting armed struggle, Sipah-e-Sahaba -- or the Guardians of the Friends of the Prophet -- was blamed by police for more than 400 killings in sectarian violence in recent years. The group also has strong ties to Afghanistan's former Taliban leaders.

Most of Pakistan's Sunnis and Shiites live together peacefully, but small extremist groups on both sides launch frequent attacks. Last week, six Shiites were killed in an attack on a bus in the southern port city of Karachi. More than 50 Shiite worshippers were killed in an attack on a mosque in the southwestern city of Quetta in July.

Since his release from prison, Tariq had become a supporter of the government of Prime Minister Zafarullah Khan Jamali, a Musharraf ally.

In tributes to Tariq, Parliament speaker Chaudhry Ameer Hussain, said the "entire house will miss him."

"He was a very upright politician. He was one of the best politicians in the assembly," said Hussain.

No arrests have been made in Tariq's killing and authorities would not blame any group or individual for involvement.

"We cannot blame anyone until we have evidence," Interior Minister Faisal Saleh Hayyat said. "We have some clues but we cannot disclose them. I can only say we are on the right track."

Hayyat added that the killers wanted to create "unrest and sectarian hatred in the country."