Sehwan - Pakistani forces killed and arrested dozens of suspects in sweeping raids overnight and into Friday, a day after a massive suicide bombing by the Islamic State group killed at least 80 worshipers at a famed Sufi shrine in the country's south.The terror attack — Pakistan's deadliest in years — stunned the nation and raised questions about the authorities' ability to rein in militant groups despite several military offensives targeting militant hideouts.The raids targeted militant hideouts and led to shootouts with insurgents that left at least 39 militants dead across Pakistan, according to three security officials who spoke on condition of anonymity to discuss the operations.Most of the operations were carried out by the paramilitary Rangers. In one raid, the troops killed 11 suspects at a militant hideout in the port city of Karachi. In another, the Rangers came under fire as they were returning from Sehwan, a town in southern Sindh province where the shrine bombing took place, and killed seven of the attackers.Other raids took place in northwestern Pakistan and also in the eastern province of Punjab. The officials said a total of 47 suspects were arrested in the raids.'Blood shall be avenged'In Thursday's attack, the suicide bomber walked into the main hall at the Lal Shahbaz Qalandar shrine in Sehwan, and detonated his explosives among a crowd of worshippers, killing 75. At least 20 women and nine children were among the dead and scores were also wounded in the explosion.The Islamic State group claimed the attack in a statement circulated by its Aamaq news agency, saying it had targeted a "Shiite gathering." The Sunni extremist group views Shiites as apostates and has targeted Pakistan's Shiite minority in the past. It views Sufi shrines like the one targeted on Thursday as a form of idolatry.Raja Somro, who witnessed the attack, told a local TV network that hundreds of people were performing a spiritual dance known as the "dhamal" when the bomber struck."I saw bodies everywhere. I saw bodies of women and children," he said.Local TV showed graphic footage of the aftermath of the blast, with wounded worshipers crying out for help and the floors covered with shoes, blood and body parts. Women cried and beat their chests in grief.Prime Minister Nawaz Sharif vowed that security forces would track down the perpetrators of the attack, according to Pakistani state TV."Each drop of the nation's blood shall be avenged, and avenged immediately," Pakistan's army chief, Gen. Qamar Javed Bajwa, said in a statement. "No more restraint for anyone."