At least nine students were killed and more than 80 wounded on October 27 in a bomb attack at a religious school in northwestern Pakistan, local officials and witnesses said.
Students had been taking a lesson when the explosion tore through the madrasah in Peshawar, some 170 kilometers west of Islamabad, said Waqar Azim, a senior police official.
"Someone took a bag inside the seminary," Azim said, adding that the person who had brought in the bag left the lecture hall before the blast.
Peshawar police chief Muhammad Ali Gandapur said the bomb contained up to 6 kilograms of explosives.
Dr. Muhammad Asim Khan, a spokesman for the Lady Reading Hospital in Peshawar, said the hospital had received seven dead bodies and nearly 70 injured so far.
"Most of those killed and injured were hit by the ball bearings and some were badly burned," he said.
All of the dead were men aged between 20 and 40, Khan said. Teachers and boys as young as 7 were among the wounded.
Teacher Safiullah Khan said more than 1,000 students are currently enrolled at the religious school, which is roughly divided into two sections, with one for students aged 18 and older and the other for children.
Some Afghan students studying at the seminary were also among the wounded, officials said.
No group claimed immediate responsibility for the attack.
Pakistani Prime Minister Imran Khan condemned the bombing and asked authorities to ensure the provision of best possible medical aid to the victims.
The Pakistani Taliban has been targeting public places, schools, mosques, and the military across the country since 2001.
Peshawar is the provincial capital of Pakistan's Khyber Pakhtunkhwa province bordering Afghanistan. It was once the epicenter of militant violence in the country.
In 2014, Pakistan's army launched a massive offensive to wipe out militant bases in the area. The offensive was stepped up after the Pakistani Taliban killed more than 150 people, the majority of them children, at a school in Peshawar in December 2014.
The province has been the scene of such militant attacks in recent years, but sectarian violence has also killed or wounded people at mosques or seminaries across Pakistan.
The attack comes two days after a bombing in the southwestern city of Quetta killed three people.
With reporting by AFP, AP, Reuters, and dpa