Story highlights One family loses 18 members in the attack

The Pakistani Taliban denies responsibility, condemns attack

At least 40 were killed and about 100 wounded in an attack on historic Pakistani bazaar

Witness: "Everything was on fire. Women and children were burning"

At least 40 people were killed and about 100 were wounded after a bomb exploded at a bazaar in Peshawar on Sunday, officials at a Pakistani hospital said.

A car carrying 220 kilograms (485 pounds) of explosives detonated in the city's historic Qissa Khawani bazaar, destroying at least 10 shops and several vehicles and leaving a huge crater, said Shafqat Malik, chief of the bomb disposal unit.

The Pakistani Taliban, Tehrik-i-Taliban, condemned the attack and denied any involvement.

Alamzeb Khan was working at a nearby tea stall Sunday when he felt the earth shake. The impact of the blast knocked him to the ground.

"When I got up, everything was on fire. Women and children were burning in (a) Suzuki pickup, and a number of vehicles were destroyed, besides the shops (that) were also on fire," Khan said.

The death toll is expected to rise, as most of the wounded are critically injured, said Dr. Arshad Javed, chief executive of Lady Reading Hospital in Peshawar.

Already, people are sharing stories of incredible loss. One family traveled to Peshawar to attend a wedding. Now they're planning a mass funeral. In all, the family lost 18 members in the attack, including children.

A gruesome week

Peshawar, the capital of Pakistan's volatile Khyber Pakhtunkhwa province, has endured a violent week.

On Monday, 81 people were killed in a suicide bombing at a Protestant church in one of the deadliest attacks ever on the Christian community in Pakistan.

A splinter group of the Pakistani Taliban claimed responsibility, saying the attack was in response to U.S. drone strikes in tribal areas.

And on Friday, at least 17 people were killed and more than 30 others wounded in an explosion that ripped through a bus carrying government employees.

Sikander Khan Sherpao, senior minister of Khyber Pakhtunkhwa, suggested the attack had been carried out by forces wanting to sabotage recent efforts by the national government to pursue peace talks with the Pakistani Taliban.

The recent bombings have raised concerns about the government's ability to provide security. Sunday evening, after a meeting of provincial officials, the creation of task forces to help maintain peace in Peshawar was announced.

No group immediately claimed responsibility for Sunday's attack at the bazaar. The Pakistani Taliban decried the loss of innocent life but at the same time struck a defiant note. "We are targeting the government machinery and the law enforcement agencies but not general public," said spokesman Shaidullah Shaid.

Qissa Khawani bazaar, or the "storytellers' market," was the site of a bloody massacre in April 1930 when British soldiers fired on peaceful demonstrators, killing hundreds. At the time, Pakistan was part of India, and India was under British rule.

Khyber Pakhtunkhwa is rife with Islamic extremists and has been the site of clashes between Pakistani security forces and militants.

Earlier this month, Pakistani officials announced plans to pursue peace talks with Taliban militants and withdraw troops from parts of the volatile northwestern region, which borders Afghanistan.