A powerful bomb tore through a busy Shiite mosque in southern Pakistan on Friday, killing close to 50 people in the country's deadliest sectarian attack in nearly two years.
The blast hit the mosque in Shikarpur in Sindh province, around 470 kilometers north of Karachi, as hundreds of worshippers attended Friday prayers.
A spokesman for the Jundullah militant group, a splinter faction of the Pakistani Taliban, said they were behind the blast. "We claim responsibility for attack on Shiites in Shikarpur very happily," the group said in a statement, AFP reported.
The blast was one of the deadliest sectarian attacks to hit the country in years and comes as Pakistan is already struggling to contain a surging militancy following the horrific Peshawar school attack that killed 150 people, most of them children, in December.
Sainrakhio Mirani, police chief of the region also said officers were working to determine whether it was a suicide bombing or whether a 6-7 kilogram bomb was detonated remotely.
Shaukat Ali Memon, the medical superintendent of Civil Hospital in Shikarpur, gave a death toll of 48. Earlier, Sindh health minister Jam Mehtab Daher said in a statement that a total of 40 were killed in the attack and 46 were wounded.
Hundreds of people rushed to the scene after the blast to try to dig out survivors trapped under the roof of the mosque, which collapsed in the explosion, according to witnesses.
Television footage of the aftermath showed chaotic rescue scenes as people piled the wounded into cars, motorbikes and rickshaws to take them for treatment.
"The area is scattered with blood and flesh and it smells of burnt meat, people are screaming at each other... it is chaos," a witness told AFP.
Local resident Mohammad Jehangir said he "felt the earth moved beneath my feet" as he prayed at another mosque around 1.5 kilometers away.
An official with a national Shiite organization, Rahat Kazmi, said up to 400 people were worshipping in the mosque when the blast struck.
The Friday blast also marked one of the bloodiest attacks in Pakistan since March 2013, when a car bomb in a Shiite neighborhood of Karachi killed 45.
The attack came as Prime Minister Nawaz Sharif visited Karachi, the capital of Sindh province, to discuss the law and order situation in the city.
Karachi, Pakistan's biggest city and economic heart, has wrestled for several years with a bloody wave of criminal, sectarian and political murders.
Anti-Shiite attacks have been increasing in recent years in Karachi and also in the southwestern city of Quetta, the northwestern area of Parachinar and the far northeastern town of Gilgit.
Around 1,000 Shiites have been killed in the past two years in Pakistan, with many of the attacks claimed by the extremist group Lashkar-e-Jhangvi (LeJ).
A report by the US Institute of Peace this week warned that sectarian militant groups were growing in strength in rural areas of Sindh, a province which has escaped much of the worst of the violence that has rocked Pakistan over the last decade.
Pakistan has stepped up its fight against militants in the past month, following the Taliban's massacre at a school in the northwestern city of Peshawar.
Heavily armed gunmen went from room to room at the army-run school murdering 150 people, most of them children, in an attack that horrified the world.
Since then, the government has ended a six-year moratorium on executions in terror-related cases and pledged to crack down on all militant groups.
