A bomb at a procession of Shia Muslims in Pakistan killed at least six and wounded another 90 on Sunday, taking the death toll from a week of Taliban blasts against the group to more than 30.
The bomb detonated as hundreds of Shia worshippers paraded through the north western city of Dera Ismail Khan to commemorate the holiday of Ashura.
The bomb was made of 17lbs of explosive laced with steel balls and appeared to have been planted in a shop along the procession route, according to police.
The Pakistani Taliban frequently attack Shias, who they consider heretics. Shia Muslims use Ashura to mourn the martyrdom of Hussein, a grandson of the Prophet Mohammed, and men often flagellate themselveswith chains and knives as an act of penance.
Large crowds drawn by the festival have become a prime target for Sunni extremists.
A similar bombing killed seven and injured 30 on Saturday, and last week a Taliban suicide bomber struck a procession in Rawalpindi, near Islamabad, killing 17.
Thousands of extra police were deployed across the country to try to stop attacks and mobile phone services had been shut down in major cities to because officials said phones were often used as remote detonators.
Meanwhile the Afghan government closed public universities in Kabul in an attempt to diffuse sectarian tension after a dormitory clash left at least two students dead and dozens wounded.
Witnesses said fighting broke out after Sunni students tried to prevent Shia classmates decorating a university mosque with black cloth as they observed Ashura.
Verbal clashes quickly escalated into violence with opposing gangs hurling rocks and beating each other up. One student reportedly died after he was pushed from an upper storey of a university building.
Gen Daud Amin, deputy commander of Kabul police, said his men arrived to find two students dead and at least 14 injured. There was widespread damage to university property.
The Higher Education Ministry on Sunday announced the three main state-run universities in Kabul would close for ten days. A source told The Daily Telegraph the order had come directly from Hamid Karzai's palace.
Afghanistan has been largely spared the sectarian bloodshed which has blighted Pakistan, but there were fears last year it could ignite when a bombing killed more than 60 Shia worshippers at Ashura. Security officials said that attack had been conducted by a little-known militant movement from Pakistan.
A tight security operation was mounted this year to prevent a repeat attack.