Thousands of Shiites across Pakistan mourned and protested today after a bombing at a Shiite mosque killed at least 59 people.
In Shikarpur, the site of the blast, mourners held a mass funeral for the dead in Friday's attack. Thousands of Shiite mourners beat their chests and heads, wailing as other non-Shiites also took part.
Shiites' organisations also held protest sit-ins in different cities across Pakistan. Television footage showed some protesters burned tyres and blocked roads, chanting slogans for the arrest of the perpetrators and protection for Shiite places of worship.
The death toll in the blast rose today after three victims died overnight from their wounds, said Abdul Qudoos Kalwar, a senior police official.
The bombing happened in Shikarpur, roughly 310 miles north of Pakistan's port city of Karachi. That area of Pakistan has suffered comparatively little violence in contrast to the north-western tribal areas bordering Afghanistan.
Friday's bloodshed raised fears that extremists could be gaining a foothold in the region.
The blast took place when about 250 worshippers gathered in the Shiite mosque for Friday prayers, Kalwar said. Dozens were wounded.
Today investigators determined a suicide bomber caused the blast, said Saqib Memon, another senior police official in Shikarpur.
UN secretary-general Ban Ki-moon was "appalled by such vicious targeting of people on account of their religious affiliation", his spokesman said in a statement.
The Sunni militant group Jundallah claimed responsibility for the attack. The militant group previously has claimed responsibility for attacks on Shiites and other religious minorities, including a 2013 double suicide bombing of an Anglican church in Peshawar that killed 85 people.
Many Sunni extremists do not consider Shiites, who represent as much as 20% of Pakistan's population, to be true Muslims.
Sunni militants in Pakistan have bombed Shiite mosques, killed Shiite pilgrims travelling to neighbouring Iran and assassinated Shiite religious figures and community leaders.