Hundreds of mourners have attended funerals in Pakistan after a suicide bombing killed at least 54 people at an election rally for a pro-Taliban cleric.

Family and friends of the victims carried caskets draped in colourful cloths to burial sites in the hills the day after the atrocity.

No-one has immediately claimed responsibility for Sunday’s bombing in Bajur that killed at least five children and wounded nearly 200 people.

The attack appeared to reflect divisions between Islamist groups, which have a strong presence in the district in Khyber Pakhtunkhwa province that borders Afghanistan.

Pakistan bomb victim
An Injured boy lies on the bed at a hospital after Sunday’s suicide attack (AP)

It targeted the Jamiat Ulema Islam party, which has ties to the Afghan and Pakistani Taliban.

At least 1,000 people, according to police, were crowded into a tent near a market for the rally ahead of elections this autumn when the blast went off.

“People were chanting ‘God is Great’ as the leaders arrived,” said Khan Mohammad, a local resident who said he was standing outside the tent, “and that was when I heard the deafening sound of the bomb”.

Mr Mohammad said he heard people crying for help, and minutes later ambulances arrived and began taking the wounded away.

Police said their initial investigation suggested that the Islamic State group’s regional affiliate, a rival of the Taliban, could be responsible, while a Pakistan security analyst pointed to breakaway factions of the Pakistani Taliban as possible suspects.

The Pakistani military spent years fighting the Pakistani Taliban, also known as Tehreek-e-Taliban Pakistan, or TTP, in Bajur before declaring the district clear of militants in 2016.

Pakistan
Shoes of victims are gathered following the explosion (AP)

But the Jamiat Ulema Islam party, headed by hard-line cleric and politician Fazlur Rehman, has remained a potent political force.

On Monday, police recorded statements from some of the wounded at a hospital in Khar, the district’s principal town.

The Islamic State in Khorasan Province, which police identified as a suspect in the attack, is based in neighbouring Afghanistan’s Nangarhar province and is a rival of the Afghan Taliban and al-Qaida.

Pakistani security analyst Mahmood Shah said some TTP members have been known to disobey their top leadership to carry out attacks, as have breakaway factions of the group.

As condolences continued to pour in from across the country, dozens of people who were injured were discharged from hospital, while the critically wounded were taken to the provincial capital of Peshawar by army helicopters.

The death toll continued to rise as some critically wounded people died in hospital, physician Gul Naseeb said.