New details about the alleged leader of the 22-hour attack on army headquarters less than 10 miles from the Pakistani capital underscored the bonds among the groups. Officials said Mohammad Aqeel, a former member of the army medical corps, had ties to the Taliban as well as to two al-Qaida-linked militant groups in the Punjab, Pakistan's dominant and most populous province.
The Punjab connection is significant because it means the Taliban may be spreading their influence beyond their traditional base of ethnic Pashtuns in tribal areas on both sides of the Afghan border. Ethnic Punjabis, by contrast, dominate the army and the major institutions of the Pakistani state. Al-Qaida is primarily Arab.
The Taliban said their Punjab faction carried out the attack in that province - the first time they had referred to such an outfit - and vowed to activate cells outside the Pashtun heartland of the lawless frontier region.
"This was our first small effort and a present to the Pakistani and American governments," Taliban spokesman Azam Tariq told The Associated Press. Tariq said the group was seeking vengeance for the killing of its leader in a CIA drone strike.
Given the nearly weekly attacks in Pakistan over the last three years, the threat of a nationwide bombing campaign was credible. The Pakistani Taliban have made outlandish claims in the past, however, and stand to benefit from exaggerating their reach.
Monday's suicide bombing took place in Shangla, a Pashto-speaking area of the Swat Valley region. The attacker was apparently targeting a military vehicle, but most of the victims were ordinary Pakistanis.
It was the deadliest attack in the region since the army claimed to have cleared the valley of militants in an offensive earlier this year. While many insurgents were killed or captured in the army offensive, others are believed to have gone to rural areas or neighboring districts.
TV footage of the bombing showed vegetable stands with their wares spilled on the street, two-story buildings with their fronts torn away and several wrecked cars.
Muhammad Alam was teaching in a nearby school when the attack took place.
"We ran out. The whole market was on fire," he said. "Bodies were lying everywhere."
The attack killed 41 people, including six security officers, and wounded 45 others, provincial Information Minister Mian Iftikhar Hussain said. There was no immediate claim of responsibility.
The Taliban have stepped up attacks in the past week as the military has been preparing to launch a major offensive against the militants in their stronghold, the border region of South Waziristan.
On Oct. 5, a bomber blew himself up inside a heavily guarded U.N. aid agency in the capital, Islamabad, killing five staffers. On Friday, a suspected militant detonated an explosives-laden car in the middle of a busy market in the northwestern city of Peshawar, killing 53 people.
The raid on army headquarters in the city of Rawalpindi began Saturday when 10 heavily armed militants shot their way past the front gate. They then seized more than 40 hostages and held them overnight in a building inside the vast compound. Commandos stormed the building Sunday. The army said nine militants and 14 other people were killed, mostly members of the security forces.
Military spokesman Maj. Gen. Athar Abbas said the attack was the work of the Pakistani Taliban and was planned in South Waziristan. The army intercepted audio of deputy Taliban leader Waliur Rehman getting an update on the attack and telling a subordinate to pray for the assailants, he said.
But he said Aqeel, the ethnic Punjabi, led the attack. Four other militants were also from outside the border area, he said.
Aqeel - also known as Dr. Usman - was captured alive, but was badly wounded and unable to talk to security forces.
He is believed to have orchestrated an ambush on Sri Lanka's visiting cricket team in Lahore this year, a failed attempt to shoot down then-President Pervez Musharraf's plane with an anti-aircraft gun and a suicide attack that killed the army surgeon general in February 2008 in Rawalpindi, said Zulfikar Hameed, a police investigator who led the team that investigated the cricket attack.
Aqeel deserted the army medical corps in 2004 to join the militants, Abbas said.
He was recruited into Jaish-e-Mohammed and Lashkar-e-Janghvi, violent groups based in the Punjab province, Hameed said. Aqeel later joined the Taliban in Waziristan and helped recruit and train militants from Punjab, Hameed said.
Jaish and Lashkar have long been blamed for attacks on Western targets in Pakistan, as well as on minority Shiites. Both groups are believed to have had links with Pakistan security agencies, which used their members to fight proxy wars in Afghanistan and India before 2001. Groups thought to be allied with them still run hardline boarding schools in the Punjab.
Abbas said the recent stepped-up attacks were aimed at making the government have second thoughts about making a big move into South Waziristan. He said the government has decided to go ahead with the offensive, and that it is up to the army when to launch it.
The surge in terror attacks follows a relatively calm September. It has dashed any hopes the militant movement would collapse in disarray after losing its leader, Baitullah Mehsud, in a U.S. missile strike in August.
Associated Press Writers Riaz Khan in Peshawar, Ishtiaq Mahsud in Dera Ismail Khan, Asif Shahzad in Islamabad and Babar Dogar in Lahore contributed to this report.