The attack occurred in Lakhi Dar area of Shikarpur just after Friday prayers when worshippers were leaving the mosque.
The explosion was so powerful that the roof of the mosque caved in, leaving a number of victims trapped under the debris. Bystanders were trying pulling out the dead and injured from the rubble.
The responsibility of the attack was claimed by Jundullah, a militant organization which has claimed most of the past attacks on Christians, Hindus, Shias and Ahmedis.
“Our target was the Shia community (mosque). They are our enemies and we will always target them,” said Fahad Marwat.
The mosque’s blood-splattered floor and walls. The ball bearings packed with the explosives made holes in the walls and ceiling.
Volunteers and distraught relatives in blood-soaked clothes were seen helping the wounded and taking them to nearby hospitals.
Sindh Information Minister Sharjeel Inam Memon told media that an emergency had been imposed at all hospitals in Shikarpur and surrounding cities.
He comfirmed that 50 people had died and over 50 injured. Many of the casualties were shifted to hospital in Sukkur and Larkana districts of Sindh.