The blast took place at a religious seminary in Pakistan’s northern city of Peshawar on Tuesday, killing at least 10 people, including children, and injuring 70 others, local sources said.

According to Pakistani police, the bomb went off minutes after an unknown person left a bag at the madrasa.

The attack happened while an Islamic scholar was delivering a lecture about the teachings of Islam at the main hall of the Jamia Zubairia madrasa.

Pakistani prime Minister Imran has released a condolences message for the victims of the attack.

“Deeply saddened by terrorist attack on madrassah in Peshawar. My condolences go to the victims’ families & prayers for early recovery of the injured. I want to assure my nation we will ensure the terrorists responsible for this cowardly barbaric attack are brought to justice asap,” Khan tweeted.