A roadside bomb targeting a minivan in Kurram Agency on Tuesday killed 14 people, a local official said, raising an earlier reported death toll of nine killed.
The blast ripped through the van travelling through a minority Shiite region of the Kurram tribal area, which borders Afghanistan, said Arif Khan, a tribal administration official in the town of Parachinar. The area has long been the scene of sectarian violence.
Five women and four children were among the 14 killed, while 10 people were wounded in the explosion. With few adequate medical facilities in the area, an Army helicopter evacuated the wounded to a nearby military hospital.
Jamat-ul-Ahrar, a breakaway Taliban faction, said it was behind the attack on the Shiites.
For over a decade, Pakistan has been fighting Islamist militants who have killed tens of thousands of people. Islamabad has also undertaken several large-scale offensives in the tribal regions in an effort to rout militants from the area.
Also Tuesday, four convicted members of the Pakistani Taliban were executed in a prison, ISPR said.
In Karachi, paramilitary forces raided an apartment following a tip that militants were hiding there, police officer Aurangzeb Khattak said.
After a seven-hour siege, three militants, including a woman, blew themselves up inside the apartment. The explosion also killed a five-year-old while a fourth militant was killed trying to flee the scene.