Updated

A homicide attacker detonated a car bomb in a market close to a politician's home in central Pakistan on Tuesday, killing 33 people and showing the increasing reach of Taliban militants in the nuclear-armed nation.

The insurgents, who are linked to al-Qaida and militants fighting U.S. and NATO troops in neighboring Afghanistan, want to topple the U.S.-allied government in Pakistan and install a hard-line Islamist regime.

Under heavy Western pressure, the Pakistani army launched an offensive against the Taliban's main stronghold in the mountains close to the Afghan border in October. The militants have retaliated with an onslaught of bombings that have killed more than 500 people, most of them civilians.

Tuesday's attack in the Punjabi town of Dera Ghazi Khan badly damaged the lawmaker's house and nearby shops and buildings, including a mosque and bank. It was unclear whether the bomber was targeting the home of the politician, who was not there at the time, or the market.

The dead and most of the injured were people shopping or working at the market.

As night fell, people searched through the debris for survivors trapped under the rubble.

"The whole market has collapsed," said Raza Khan, a local resident. "There is smoke and people running here and there."

Rescue official Natiq Hayat said 33 people were killed and 60 wounded. Government official Hasan Iqbal said the attack was carried out by a homicide bomber.

The attacker had packed the car with about 900 pounds (400 kilograms) of explosives, senior police officer Mohammad Rizwan said.

The lawmaker whose home was hit, Zulfiqar Khosa, is a senior member of the Pakistan Muslim League-N party, which is in charge of the Punjab government but is in the opposition in the federal government.

Police and politicians in Punjab are under pressure to crack down on militant networks that have long recruited in its poor villages and Islamic boarding schools.

The militants have staged several attacks in Punjab, far beyond the northwestern tribal regions bordering Afghanistan. Dera Ghazi Khan district is in Punjab but borders the country's other three provinces.

Zulfiqar Khosa's son, Dost Mohammad Khosa, said two of his cousins were among the wounded.

"It was a direct attack on us," Dost Mohammad Khosa alleged, declining to speculate who was behind the blast.

Iqbal said he doubted the house was the target, speculating that the attacker simply wanted to spread terror in the town.

Militants have mostly targeted security forces in recent months, but lawmakers and court buildings also have been attacked. There have also been at least three bombs in crowded markets, apparently aimed at causing civilian casualties and undercutting public support for the army offensive.