The blast took place in a satellite town of Quetta, the province's main city. Debris and shattered glass littered the scene.
See ? Even the daesh know where to find Taliban. Doha...sheesh !
Fida Mohammad, who was attending evening prayers, said about 60 people were present at the time of the attack on the mosque, which is located in a densely populated area.
The explosion ripped through the front row of worshippers seconds after the prayer began, he told AFP.
I knew being a backbencher to islam had its pros.
"It was a powerful blast, people were screaming and running here and there - many people were injured because of the stampede," Mohammad said.
Mohammad Waseem, a doctor at Quetta's Sandeman hospital, confirmed that 15 victims had died.
The police chief of Balochistan province, Mohsin Hassan Butt,
Chief Butt. Nice ring to it.
also confirmed the death toll, telling AFP: "Nineteen people are still taking medical treatment, the condition of three to four is critical."
A police officer was among the dead, he added.
Provincial home minister Zia Ullah Langu told reporters that investigations by bomb disposal officers indicated that a suicide bomber carried out the attack.
A spokesman for the provincial government, Liaqat Shahwani, confirmed a suicide bomber was to blame.
'And may all seven pieces of him be cursed from this day on !'
The Islamic State claimed responsibility for the attack, according to the SITE intelligence group.
A Pakistani military spokesman said on Twitter that paramilitary personnel has reached the mosque and cordoned off the area.
"A joint search operation with police is in progress, injured being evacuated to hospitals," said the spokesman, Asif Ghafoor.
The attack comes two days after a motorcycle bomb targeting a paramilitary force vehicle killed two people and wounded 14 others at a busy market in Quetta.
