Updated

The government announced bounties Thursday for 21 leaders of Taliban militants in northwestern Pakistan, after saying that a massive gun and bomb attack that killed about 30 people in the east was likely linked to the insurgency.

The attackers — using guns, grenades and a van packed with explosives — targeted police and Pakistan's intelligence agency in the city of Lahore. Some 250 people were wounded in the Wednesday morning assault and blast, which mangled dozens of cars left a huge crater.

The attack in Pakistan's second-largest city, the capital of the Punjab province, was far from the restive northwest Afghan border region where the Taliban have established strongholds in Swat and other places and have faced a month-old army offensive.

It also was the third deadly assault since March in Lahore, a major intellectual and cultural center in Pakistan, following deadly assaults on the visiting Sri Lankan cricket team and a police academy.

Officials fear militants may be choosing targets there to make the point that nowhere is beyond their reach.

A group calling itself Tehrik-i-Taliban Punjab, or Taliban Movement in Punjab, took the blame for the bombing in a Turkish-language communique posted on Turkish jihadist Web sites Wednesday and referenced the fight in Swat, the SITE Intelligence Group said.

The claim could not be verified, and the militant group's relationship to the Taliban was unclear.

Interior Minister Rehman Malik said militants were striking out because they were losing the fight with government forces battling to uproot extremists in the northwestern valley and tribal areas near Afghanistan.

"I believe that anti-Pakistan elements, who want to destabilize our country and see defeat in Swat, have now turned to our cities," Malik told reporters.

Officials said three suspects had been detained.

Washington and other Western allies back the Swat campaign and are watching it closely, seeing it as a test of Pakistan's resolve to combat the spread of extremism in Pakistan.

The government took out ads in several newspapers Thursday listing 21 Taliban leaders — 18 of them with pictures — and offering varying rewards for each, the lowest being around $12,400. The top bounty was $62,000 for top Swat Taliban leader Maulana Fazlullah.

Police and government officials in Lahore described a coordinated assault on a compound that housed several official buildings, including a Punjab provincial government office and buildings housing the Inter-Services Intelligence agency, or ISI.

A white van pulled up in a narrow street separating the police and ISI buildings, police officer Sohail Sakheera told The Associated Press. Two gunmen stepped out from either side of the van, took cover behind concrete barriers protecting the buildings and opened fire, one on the ISI building, the other at the police building. A grenade was lobbed at the ISI building, he said.

A driver remained in the van.

Security guards returned fire and the fighting lasted several minutes, until one of the attackers was hit by ISI sharpshooters. Then a huge explosion erupted as the bomb was detonated.

"The moment the blast happened, everything went dark in front of my eyes," witness Muhammad Ali said.

The police building collapsed, crushing some officers and trapping others. Walls were sheared off the ISI building.

A crater several yards in diameter and several feet deep marked the exact spot of the blast, which provincial government official Sajjad Bhutta said was caused by 220 pounds of explosive.

Raja Riaz, a senior provincial government minister, told reporters about 30 people were killed and at least 250 wounded. Fifteen police and several intelligence agents were among the dead, officials said. The remainder of the dead and the bulk of the wounded were civilians caught in the blast or hit by shrapnel.