Islamabad and Karachi - Sufi devotees have returned to their shrine in Pakistan's southern Sindh province less than a day after it was targeted in a suicide attack, in defiance of ISIL which claimed the bombing.

Thursday's blast , which killed at least 88 people and wounded hundreds as they performed a ritual, was the worst attack on Pakistani soil since a 2014 school attack in the northwestern city of Peshawar, which killed at least 154, mostly children.

On Friday evening, about 150 residents of the southern town of Sehwan returned to the shrine of Syed Muhammad Usman Marwandi, better known as Lal Shahbaz Qalandar, a revered 13th-century Sufi philosopher and poet who is venerated by millions across South Asia.

Caretakers washed and cleaned the white marble floors, which were streaked with blood and scattered debris, as others prepared for the evening ritual of the dhamaal - a form of devotional percussion and dance.

As the drums began, the faithful raised their arms and began the ritual, moving rhythmically to the quickening beat.

"This is Lal Shahbaz Qalandar , any terrorist, any number of terrorist attacks will not scare us. The dhamaal will continue, and must continue," said Ali Otho, a worshipper.

This is Lal Qalandar Shahbaz, any terrorist, any number of terrorist attacks will not scare us. The dhamaal will continue, and must continue Ali Otho , worshipper

Devotees said they would not allow anyone, attackers nor police seeking to secure the location, to stop them from praying at the grave of their patron saint.

"This is no place for the police," said Haja Shah, one of the shrine's caretakers, with tears in his eyes. "This is our place."

Security forces, meanwhile, launched a series of raids following the attack, killing at least 100 people , all identified as "terrorists".

Al Jazeera was unable to independently verify that figure, which was cited in a military in a statement on Friday.

The raids followed the closure of Pakistan's border with Afghanistan , where the government says Tehreek-e-Taliban Pakistan (TTP) and other armed groups enjoy safe havens.

On Friday, Pakistan handed Afghanistan a list with the names of 76 "terrorists", demanding immediate action be taken against them.

The "terrorists" in hiding were planning, directing and supporting fighters across the border, the statement explained.

In a call to the commander of the US-led NATO force in Afghanistan, General John Nicholson, Pakistani army chief General Qamar Javed Bajwa hinted at the possibility of pursuing operations within Afghan territory if action was not taken.

"Such terrorist activities and inaction against them are testing our current policy of cross-border restraint," Bajwa said , according to a statement.

Wave of attacks

Armed groups such as the Pakistani Taliban and others have often targeted shrines for not conforming to their strict, literalist interpretation of Islam .

In November, ISIL, or the Islamic State of Iraq and the Levant group, claimed responsibility for a suicide attack on a shrine in a Balochistan town, killing at least 52 people.

Thursday's attack was the latest in a wave of violence this week that has claimed more than 100 lives.

On Monday, at least 13 people were killed when a suicide attacker targeted police at a protest in Lahore , the country's second-largest city.

On Tuesday, two police officers were killed while trying to defuse a bomb in the southwestern city of Quetta.

On Wednesday, two suicide attacks in the northwestern city of Peshawar and the Mohmand tribal area claimed at least six lives.

On Thursday, in addition to the 88 killed at the shrine, at least seven security forces personnel were killed in two separate attacks in Dera Ismail Khan and Awaran.

Roots of violence

Much of that violence, with the exception of Thursday's attack on the Sufi minority, was claimed by the Pakistan Taliban's Jamaat-ur-Ahrar faction, which has worked with ISIL, also known as ISIS, in the past but remains separate from it.

"Pakistan has underestimated the potential for ISIL here," Zahid Hussain, a veteran Pakistan journalist and security analyst, told Al Jazeera.

"Authorities always said that ISIL could not create an organisation here, but there are already organisations operating in Pakistan that agree with their ideology, like the Lashkar-e-Jhangvi and others."

Pakistan has repeatedly blamed Afghanistan for giving safe haven to fighters on its side of the border, and vice versa.

However, analysts say that trading blame is proving counterproductive.

"The real issue is that the attacks are happening here. The networks are here, the facilitators are here … it is a flawed view that all of these attackers are coming from Afghanistan," said Hussain.

"The people are here."

Mosharraf Zaidi, former adviser to Pakistan's foreign ministry, told Al Jazeera: "It doesn't help anybody to fixate on the problem of Afghanistan as being the only problem that we face.

While there are groups that use safe havens in Afghanistan, the "core of problem Pakistan faces today is inside Pakistan".

The "network of terrorists exists in this country", he explained, and the "solution is also inside Pakistan".

Hussain said while a Pakistani military operation has succeeded in dislodging the Pakistani Taliban from its headquarters, the group's networks with other armed groups - including those targeting minorities and Indian security forces in Kashmir - remain intact.

"This is not unexpected because half-hearted measures always lead to these situations," he said.

"The real issue was the network of militants in the heartland, in the main cities. They were intact, and even though we have been hearing reports of thousands arrested ... what happens to them?"

Hussain's views were echoed by Ijaz Khan, a professor at Peshawar University and security analyst.

"What happened when [the military operation] started: terrorists of different organisations felt the pressure and some of their safe havens were destroyed," he told Al Jazeera.

Sounding a warning of further attacks, he said: "They were dislocated, but not finished. Now, they have regrouped themselves."

With additional reporting by Wali Muhammed in Sehwan



