A suicide bomb destroyed a Pakistani mosque on Friday, killing 61 people during the main weekly prayers and trapping human remains under a collapsed roof and pulverised rubble.

People gather at a mosque in Akhurwall village, Pakistan, on November 5 after a suicide bomb tore through the building. The blast during the main weekly prayers killed 61 people and left human remains trapped under a collapsed roof and pulverised rubble.

The attack in the volatile northwest was the deadliest in the nuclear-armed country on the front line of the US-led war on Al-Qaeda in two months. Dozens of people were critically wounded and officials fear the toll could rise.

The attack turned the worship into a blood bath in Akhurwall village, part of the semi-tribal northwest area of Darra Adam Khel, about 140 kilometres (90 miles) west of the Pakistani capital Islamabad.

A local official said 11 children were among the dead and an AFP reporter said the force of the explosion reduced the mosque to a pile of rubble.

Only one wall was left standing and the concrete roof collapsed, leaving blood stains, human remains and hair scattered in the rubble.

Houses near the mosque were also damaged, including that of Wali Mohammad, the leader of a local pro-government militia that had clashed repeatedly with local Taliban militants until reportedly cutting a deal earlier this year.

Although the Taliban denied responsibility, a local elder blamed the group and suggested it could have been acting to punish Mohammad\'s militia.

Witnesses said the bomber walked into the mosque and shouted Allahu akbar (God is greater) before a deafening explosion.

Dilawar Gul, 30, said he was collecting donations from worshippers when he heard the suicide bomber shout.

"Then I heard a huge blast which flung me to part of the mosque where the roof didn\'t collapse, and I survived."

Local administration official Gul Jamal Khan told AFP that 61 people were killed and 104 others were wounded.

"The number of wounded is more than 100. The dead include 11 children. Some of the bodies are beyond recognition."

Shahid Ullah, district administration chief of the northwestern garrison town of Kohat also confirmed the death toll.

Ambulances and private volunteers rushed to take the victims to hospital in Peshawar, the main city in the northwest.

Television footage showed an elderly bearded man wearing a traditional white shalwar khamis drenched in blood limping into casualty, while a woman shrieking in grief beat her hands against her head.

A private car sped up to the main Lady Reading Hospital with a volunteer sitting next to a body in the boot.

Local tribal elder Sohbat Khan Afridi blamed the Taliban, given that Mohammad, who formed a tribal militia in 2007 to rise up against the militants, has a house close to the mosque, although he is understood to live in Lahore.

The Taliban and the militia, which is known locally as a lashkar, clashed repeatedly in the area but this year reached some kind of compromise in which blood money was paid to the Taliban, Afridi said.

He declined to go into further details saying only: "The lashkar apologised to the Taliban because they did not have the means to defeat the Taliban."

But Azam Tariq, spokesman for Pakistan\'s Tehreek-e-Taliban, denied that the faction was involved. The Taliban routinely deny attacks that kill civilians but have been blamed for some of the country\'s most devastating bombings.

"It is the work of Blackwater," Tariq told AFP by telephone from an undisclosed location in reference to the US security firm renamed Xe after courting controversy in Iraq over civilian deaths.

Umarzai suggested the attack could have been retaliation for military operations targeting Islamist militants.

"An operation is going on by the army and Frontier Corps (paramilitary) in the Darra Adam Khel area. We had been expecting such attacks."

Around 3,800 people have been killed in suicide attacks and bombings, blamed on homegrown Taliban and other Islamist extremist networks, since government troops stormed a radical mosque in Islamabad three years ago.

The United States is holding out two billion dollars in fresh military aid to Pakistan, where it wants the military to do more to fight insurgents crossing into Afghanistan and fuelling a nine-year Taliban uprising there.

Washington brands Pakistan\'s northwest tribal area an Al-Qaeda headquarters, although there has been a relative lull in violence after Pakistan suffered catastrophic floods in late July that affected more than 20 million people.

Friday\'s bombing was the deadliest in Pakistan since a suicide attacker slaughtered 60 people at a Shiite Muslim rally in the southwestern city of Quetta on September 3.