Police say Blast in Pakistan's Capital Wounds 4

A Pakistani police officer tries to keep media away from the site of an explosion in Islamabad, Pakistan, Thursday Oct. 9, 2008. An explosives-laden vehicle blew up an anti-terrorist squad building and wounded at least four people Thursday in a police complex in Pakistan's capital just moments after a man delivered sweets to the facility, officials said. (AP Photo/Emilio Morenatti )

ISLAMABAD, Pakistan - An explosives-laden vehicle blew up an anti-terrorist squad building and wounded at least four people Thursday in a heavily guarded police complex in Pakistan's capital, officials and a witness said.

It appeared to be a suicide attack and investigators were probing whether the delivery of candy to the facility by an unknown man was linked, Islamabad Police Chief Asghar Gardaizi said. Some body parts were found that might belong to a suicide bomber, he said.

The incident happened as lawmakers gathered for a briefing on the security situation in Pakistan, a U.S. ally in the war on terror that is besieged by militancy. The capital has been under tight security because of the private session.

"It seems to be a suicide attack," said Islamabad police offical Mohammed Sadiq, who confirmed the casualty toll.

Ambulances streamed into the smoke-filled Police Lines neighborhood after the blast. The front section of the three-story, red-brick building was destroyed and a staircase had collapsed. Shoes were flung among the rubble. Police officer Suhail Iqbal said the building housed an anti-terror squad. It stood fairly deep inside the complex.

Gardaizi said at least four people were hurt; others put the wounded toll as high nine.

Gulshan Iqbal, a police commando, told The Associated Press he was sitting at a nearby barrack when a "Suzuki car hit the ant-terror squad barrack and exploded with a big bang."

He said because many officers were guarding the parliament and other areas of Islamabad, the main building was largely empty. "About 10 people were inside at the time and we saw six or seven injured," he said.

Gardaizi said a man in a green car drove to the building, went inside and handed boxes of candy to a person inside. Within moments, the explosion happened, Gardaizi said. It was unclear what happened to the delivery man. The police chief said authorities would probe why a civilian vehicle was allowed in the area.

According to military data released last month, suicide attacks have killed nearly 1,200 people in Pakistan since July 2007, most of them civilians.

The statistics also said that 1,368 security force personnel have been killed since late 2001, when Pakistan's former military ruler, President Pervez Musharraf, allied the country with Washington in its war on terror.

The violence has largely been concentrated in the northwest regions bordering Afghanistan, where al-Qaida and Taliban fighters have bases, but the insurgents have shown they can reach farther. On Sept. 20, a suicide truck bombing of the Marriott Hotel killed 54 in the city.

Pakistani lawmakers were at the Parliament building for a question-and-answer portion of the briefing by military officials about the domestic threat posed by militants.

The young civilian government called the joint Parliament session in an effort to build a national consensus on the Muslim nation's role in the U.S.-led war on terror.

Many in Pakistan believe the alliance with the U.S. has increased violence in their nuclear-armed country. The U.S. has shown impatience with Pakistan by launching cross-border missile strikes against militant hide-outs in the northwest, where al-Qaida leader Osama bin Laden is rumored to be hiding.

On Wednesday, lawmakers were shown images of militants killing people, according to two attendees who requested anonymity because like others at the meeting they were sworn to secrecy. Statistics on militancy were also given, one said, declining to divulge specifics.

Ahmed Shujaa Pasha, an army general tapped to take over Pakistan's main spy agency in the coming days, gave the briefing. The topics included Pakistan's military offensives against insurgents in tribal regions bordering Afghanistan.

Speaking in general terms, some politicians said the briefing Wednesday was superficial.

"It was more like the description of the symptoms than diagnosis of the disease," Khurram Dastagir, a member of the opposition party of ex-Prime Minister Nawaz Sharif, told Dawn News TV. "I am seeking to find out what is causing this extremism and how did it come about."

Pakistan's attorney general, Sardar Latif Khosa, said Thursday's session was arranged to allow lawmakers to ask questions. He said the meetings could go on for several more days.

Concrete barriers and barbed wire ringed a wide perimeter around the Parliament building. Members of the media were not allowed in.