Pakistan's minority Shia Hazara community on Monday refused to bury victims of a devastating bombing in Quetta that claimed 89 lives till the army takes control of the southwestern city to prevent terror attacks.

Thousands of Shias joined a protest with the bodies of some of the 89 people killed in Saturday's attack at Hazara Town in Quetta, the capital of the restive Balochistan province.

The banned Lashkar-e-Jhangvi claimed responsibility for the bombing.

A bomb containing hundreds of kilogrammes of explosives ripped through a crowded market in Hazara Town on Saturday.

Many women and children were among the dead. About 200 people were injured by the blast, which flattened several buildings. The death toll in the attack went up to 89 on Monday after four more people succumbed to their injuries.

Leaders of the Shia Hazara community, which has been repeatedly targeted by sectarian groups like the LeJ, gave the government a 48-hour ultimatum to launch an army operation against terrorists.

They accused elements of the security establishment of sheltering the militants.

Quetta police chief Wazir Khan Nasir said officials were engaged in negotiations with the Shia leaders to convince them to bury their dead.

However, Shia leader Qayyum Changezi said the protesters would not bury the dead "until a targeted operation is launched" against terrorists.

Syed Muhammad Hadi, a spokesman for an alliance of Shia groups, said the community wanted security in Quetta to be handed over to the army and targeted operations against terrorists and their supporters.

Pakistan's biggest city and financial hub Karachi was paralysed on Monday after a series of sit-ins by Shia groups and incidents of violence in several areas to protest the deadly bomb attack in Quetta. Police and rangers had to resort to shelling and water cannons in some areas.

Meanwhile, a large number of Shias, including women and children, also refused to end their sit-in outside Governor's House in Lahore against the killing of Shia Hazaras in Quetta.

The protesters said their agitation would continue till security in Quetta was handed over to the army.

The paramilitary Frontier Corps is responsible for security in Balochistan but Shias say it is unable to protect them.

After 92 people were killed in a twin suicide bombing in another Shia neighbourhood of Quetta last month, Shia Hazaras had refused to bury their dead till the federal government took steps to protect them.

Their protest triggered similar demonstrations in cities across Pakistan and Prime Minister Raja Pervez Ashraf was forced to dismiss the provincial government and impose Governor’s Rule in Balochistan.

Shia leaders said the security situation had not improved despite the imposition of Governor’s Rule.

Federal Religious Affairs Minister Khurshid Shah today said the latest attack on the Shias had highlighted the failure of intelligence agencies.

Protests against the bomb attack were organised in several cities, including Islamabad, Lahore, Jacobabad and Larkana. Markets were closed at some places and Shia groups organised rallies.

A strike was observed in Quetta on Sunday at the call of the Hazara Democratic Party.