Media playback is unsupported on your device Media caption The BBC's Emily Thomas says there were two explosions in quick succession

At least 57 people have been killed after two bombs exploded in a market in northern Pakistan, reports say.

The explosions took place in Parachinar, the main town of the Kurram tribal region, near the Afghan border.

The two blasts occurred close to two different mosques in the town, according to Reuters news agency.

More than 150 people have been injured. The area was thronged with evening shoppers, buying food for the breaking of the Ramadan fast.

A hospital doctor, Zahid Hussein, told the Associated Press that there was no place to keep the wounded, and many of them were lying on the floor and on the lawn.

A police spokesman, Fazal Naeem Khan, told the agency that one of the bombs was believed to have been planted on a motorcycle.

Sunni and Shia Muslims Muslims are split into two main branches, the Sunnis and Shias

The split originates in a dispute soon after the death of the Prophet Muhammad over who should lead the Muslim community

There are also differences in doctrine, ritual, law, theology and religious organisation

The great majority of Muslims are Sunnis

Pakistan - where Shias are a minority - has a history of sectarian bloodshed dating back to the 1980s Formidable power of anti-Shia militants Pakistan's evolving sectarian schism The Pakistani tribe that is taking on the Taliban

Explosives experts were still examining the site, he said.

A witness in the area where the second bomb went off told AP that he saw a teenage boy shout "God is great!" moments before the explosion.

The remote tribal region of Kurram is a sliver of Pakistani territory surrounded by Afghanistan. Its western tip is just 90km from the Afghan capital Kabul.

The area has a significant Shia population - a minority elsewhere in Pakistan - which has been subject to attacks by Sunni militant groups.

Bodies found

Earlier on Friday, security officials in the neighbouring Khyber tribal region said they had found the bodies of 20 suspected militants killed during a recent offensive.

The bodies were found during a search operation at Akakhel village.

Military helicopters and artillery guns had been shelling suspected militant hideouts in the area for the last five days. Officials said five soldiers were also killed during the operation.