Story highlights Pakistan says more than 100 killed in terror crackdown

ISIS affiliate in Afghanistan and Pakistan claimed responsibility for attack

Islamabad, Pakistan (CNN) Pakistan's military has launched a crackdown on what it says are terrorists with ties to Afghanistan after a suicide attack on a packed shrine in the southern city of Sehwan killed at least 88 worshipers.

The number of people injured in Thursday's attack on the famed Lal Shahbaz Qalandar shrine has climbed to 200, Fazal Pechuho, health secretary for Pakistan's Sindh province, said Friday.

Of the dead, 24 were children ages 4 to 8. Another 16 of the victims were women, according to Dr. Zahid Hussain, a local hospital official.

Pakistani soldiers cordon off Lal Shahbaz Qalandar shrine in Sehwan after Thursday's attack.

Thousands of worshipers, including families with children, had gathered Thursday at the more than 800-year-old shrine for the Sufi ritual of Dhamal, which involves music, chanting and prayer.

The Islamic State Khorasan, ISIS' affiliate in Afghanistan and Pakistan, claimed responsibility for the bombing in a phone call to CNN.

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