As Pakistan began burying its dead Monday, authorities counted 29 children among those killed by an Easter suicide bombing in an amusement park, victims of a terrorist attack that has re­inforced growing feelings of dread here.

Although 2015 was relatively quiet, horrified Pakistanis are again asking what their government can do to protect them from extremist violence.

More than 70 people in all were killed in the devastating attack Sunday in Lahore. Officials vowed to hunt down the Islamist militant bombers who claimed they targeted Christians — yet killed many of their Muslim brethren in the bargain.

Even after a week of terrorist violence in Iraq, Turkey and Belgium, the attack here nonetheless became a focus of global dismay.

It was the country’s worst terrorist attack this year and the deadliest attack in Pakistan since nearly 150 were killed at a school in Peshawar in late 2014 — a shock to the nation that led to an unexpectedly peaceful 2015. That calm period now seems to be over.

Security forces arrested a “number of terrorist suspects and facilitators” in at least five separate raids in cities across Punjab province, where Lahore is located, according to Lt. Gen. Asim Bajwa, an army spokesman. ­Bajwa also said that “a huge cache of arms and ammunition” was recovered in the operations, but he did not say where the weapons stockpile was found.

Police in Lahore said Monday that they were investigating whether the suicide bomber — who detonated an explosives-packed vest in the crowded park Sunday evening — had accomplices. The blast ripped through crowds of families celebrating Easter and a school break, transforming a joyful scene into a spectacle of chaos and horror. The city was in a period of official mourning Monday, with schools and markets closed and little traffic.

At the Vatican, Pope Francis on Monday decried the Easter bombing as “vile and abominable” and called for Pakistan’s religious minorities to be protected. He urged authorities in Pakistan to “make every effort to restore security and serenity” to Pakistanis, according to the Vatican’s website.

Pakistani authorities noted that more Muslims than Christians were killed and injured. Of those who died at the scene, 14 were Christian, 44 were Muslim, and nine could not immediately be identified, according to Muhammad Iqbal, the superintendent of police for operations in Lahore.

Prime Minister Nawaz Sharif arrived in Lahore, which is one of his political strongholds, to visit the wounded in one of the city’s many hospitals, his office said. He also announced that he was canceling a trip to Washington, where he had planned to attend this week’s nuclear summit.

A splinter faction of the Pakistani Taliban, Jamaat ul-Ahrar, claimed responsibility for the attack, saying, “It was our people who attacked the Christians in Lahore, celebrating Easter.”

It's not the first time that the Pakistani Taliban or its splinter group, Jamaat ul-Ahrar, targeted Pakistan's most vulnerable. (Jason Aldag/The Washington Post)

Pakistan, a country of 190 million, has suffered for years from sectarian violence and Islamist militancy, including a Taliban-led insurgency in the tribal areas on the border with Afghanistan. Recent terrorist attacks targeting minorities and schools have left many ordinary Pakistanis scared and on edge.

“This shouldn’t be happening,” said Rani Farzand, a teacher and neighbor of an 8-year-old girl who died in the blast. “The kids are not safe in the parks, in the schools, in the mosques. Where should we send our children? What should we do?”

On Monday, little remained of the carnage at Gulshan-e-Iqbal park, a leafy oasis in Pakistan’s second-largest city.

Police had cordoned off the bloodstained area between a fountain and a bumper-car ride in the children’s amusement section where the bomb exploded. Objects were left like small grace notes — a jeweled sandal, mangled reading glasses, a child’s shoe.

At Jinnah Hospital in Lahore, where about half of the more than 300 injured were taken Sunday night, 67 remained hospitalized with a variety of injuries, including burns and shrapnel wounds, doctors said. Politicians and TV anchors weaved among the beds, where occupants were labeled “blast victim.”

Among them were two small children, their beds marked with signs saying “unknown.” Their family died in the blast, and they had yet to be linked with other relatives.

Some were clearly still in shock. Zeeshan Taaj, 23, had been walking through the park on his way back from a pickup cricket match when the bomb detonated. He injured his leg in the aftermath and is trying to come to terms with what he saw: “Fire and smoke,” he said. “I have seen chopped legs blown off, heads and dead bodies scattered all around me.”

A friend tried to comfort him by tucking a sheet around his still-bloodied leg wound.

In another bed, Tasleem Sultan, 40, described how she and four other adult family members took eight children to the kiddie amusement park Sunday night and found it bustling on the warm evening. Her niece, Zainab, 8, had donned her best red dress and put flower-shaped barrettes in her hair for the occasion. She rode an elephant on the merry-go-round. She was holding her aunt’s hand when the force of the explosion separated them.

Later, her father found Zainab, bleeding and lifeless.

“I was weeping. I am still in shock,” Jamshaid Iqbal, 35, said in an interview at his family home after her funeral. “Why isn’t the government protecting us?”

In Islamabad on Monday, thousands of Muslim demonstrators protesting the execution of Islamist assassin Mumtaz Qadri staged a sit-in inside the capital city’s “Red Zone,” which is home to a number of vital government institutions, including Parliament and the prime minister’s house. Qadri assassinated Punjab’s governor, Salman Taseer, in 2011 over the latter’s opposition to Pakistan’s blasphemy laws.

Most blasphemy cases are lodged against non-Muslims for violations such as desecrating the Koran, Islam’s holy book, according to rights monitors. The army was deployed Sunday night to protect government buildings after the protesters rampaged across the city, damaging property and setting buildings on fire.

Erin Cunningham in Kabul, Babar Dogar in Lahore, and Haq Nawaz Khan and Aamir Iqbal in Peshawar, Pakistan, contributed to this report.

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