The blast left 150 people injured.

Peshawar Commissioner Riaz Mehsood confirmed to Dawn News that the casualties, adding that a rescue operation was underway inside the mosque.

“An emergency has been imposed at hospitals across the city and injured persons are being provided the best medical facilities,” the senior official said.

Meanwhile, Lady Reading Hospital spokesperson Mohammad Asim told Dawn News that a number of injured persons were in critical condition.

Speaking to the media, Capital City Police Officer (CCPO) Peshawar Muhammad Ijaz Khan told Dawn News that the roof of the mosque collapsed after the blast. “A number of jawans are still stuck under the rubble and rescuers are trying to pull them out.”

“The smell of explosives has been detected but it is too early to say anything substantial,” he said.

Khan said between 300 to 400 police officials were present in the area at the time of the blast.

“It is apparent that a security lapse occurred,” the CCPO told the media.

He added that the bodies and injured persons have been moved to the LRH.

The blast occured around 1:40pm as Zuhr prayers were being offered.

No group has claimed responsibility for the blast so far.

It is still not clear whether the bomb was planted inside the mosque or it was a suicide attack.

Ex- Pakistan PM Imran Khan condoled the loss of lives in the tragedy and tweeted: " Strongly condemn the terrorist suicide attack in police lines mosque Peshawar during prayers. My prayers & condolences go to victims families. It is imperative we improve our intelligence gathering & properly equip our police forces to combat the growing threat of terrorism."