A senior Pakistani police official says the death toll from an Islamic State (IS) suicide bombing at a crowded Sufi shrine in southern Pakistan has risen to 80 people, as Pakistan's political and military leaders said they would go to any length to crush Islamic extremists.
Aid workers at the scene of the tragedy say at least 30 children were among those killed on February 16, while more than 100 people were wounded.
Prime Minister Nawaz Sharif condemned the massacre as an attack on the future of "progressive, inclusive" Pakistan and vowed to do "anything possible" to protect the country, his office said.
Military chief Qamar Bajwa vowed to step up ongoing offensives against Taliban rebels, saying every drop of blood would be avenged.
A spokesman for the medical charity Edhi said the attacker appeared to have targeted the women's wing of the Lal Shahbaz Qalandar shrine, and children who were accompanying their mothers at the time of the attack had been killed.
The attack at the Lal Shahbaz Qalandar shrine is the deadliest in a wave of bombings to hit Pakistan during the past week as the Pakistani Taliban and other extremist Islamist militants carry out threats of a new offensive.
A post on the IS-linked Aamaq website claimed responsibility for the attack.
Thousands of devotees of Qalandar - a Sufi philosopher and poet -- visit his tomb in Sehwan Sharif every Thursday -- and the shrine was particularly crowded on February 16, just three days before the 742nd anniversary of his death on February 19, 1275.
Three Days Of Mourning
One woman who survived the attack told the Dawn TV news channel that she was part of a group that was visiting the shrine "for the love of our saint, for the worship of Allah."
The woman, speaking with her head scarf streaked in blood, asked, "Who would hurt us when we were there for devotion?"
The government of Sindh Province on February 16 announced a three-day mourning period.
Meanwhile, Pakistani security officials say they have closed the Torkham border crossing into Afghanistan for an indefinite period for "security reasons."
A statement from Pakistan's Interservice Public Relations agency (ISPR), the military's media wing, said that "terrorist attacks were being executed on directions from hostile powers and from sanctuaries in Afghanistan."
Major General Asif Ghafoor, the director-general of the ISI's public relations media wing, said the border crossing on the highway between Peshawar, Pakistan and Jalalabad, Afghanistan, would remain closed until "further orders."
Earlier on February 16, a land-mine blast had killed an army captain and two army soldiers in the Awaran area of Balochistan Province.
On February 15, two suicide attacks took place in northern Pakistan -- both claimed by Taliban militants.
One was in the Mohmand tribal district and the other, in the city of Peshawar, targeted court judges.
On February 13, a suicide attacker targeted protesters in the city of Lahore, killing 13 people, including senior police officers, and wounding more than 80 people.
With reporting by Reuters, AP, AFP, Dawn TV, and Geo TV