The Pakistani Taliban says it carried a suicide bombing that killed more than 50 people during a religious procession in the western city of Quetta.
Nearly 80 others were injured in the explosion at a Shia Muslim rally, the BBC reports.
It was the second Taliban attack on Pakistan's Shia Muslim minority this week - bombs in Lahore on Wednesday killed dozens.
The bombings come at a time when Pakistan is grappling with unprecedented floods that have displaced millions of people.
Organised by the Shia Imamia Students' Organisation, the rally was one of many that take place in Pakistan each year on the last Friday of the Muslim holy month of Ramadan to support the Palestinian demand for a homeland.
Shia Muslims make up an estimated one in five of Pakistan's Sunni-dominated population of 160 million.
The Taliban say the bombings are in revenge for the killing of a Sunni leader last year.