The explosion occurred in a Shiite Muslim congregation hall during Friday prayers. Videos on social media showed people fleeing while others lay bloodied on the carpeted floor, surrounded by rubble and broken glass.
"There were bodies everywhere. Some were missing arms, some were missing legs," eyewitness Syed Ashfaq told the BBC.
According to unconfirmed police reports, a suicide bomber was behind the attack. No one has claimed responsibility, but terrorist groups such as IS and Tehreek-e-Taliban (TTP) have been accused of previous attacks against Pakistan's Shiite minority.
"Targeting shrines and civilians is a heinous crime against humanity and a clear violation of Islamic principles," Foreign Minister Ishaq Dar wrote on X.
