TEHRAN, Iran (AP) — The death toll from a stabbing attack at the most revered Shiite shrine in Iran rose to two on Thursday after another cleric succumbed to his wounds, Iran’s state TV reported.

The victim, identified only by his last name, Daraei, died at a hospital in the holy northeastern city of Mashhad, after being stabbed at the city’s Imam Reza shrine on Tuesday.

The man was one of three clerics stabbed at the shrine, a rare act of violence at the major pilgrimage site for Shiite Muslims. One cleric died almost instantly; his funeral was held on Thursday. The third cleric remains in hospital.

The police have not offered a motive for the stabbing. The country’s interior minister, Ahmad Vahidi, described it on Thursday as a “terrorist attack” and vowed Iran would pursue the perpetrators and all “takfiris,” a term used for Sunni extremists who consider other Muslims infidels.

Police have not identified the assailant or the four others they arrested on charges of collaboration. But Iran’s semiofficial Tasnim news agency identified the attacker as an Uzbek national named Abdollatif Moradi. It said he had entered the country illegally through Pakistan a year ago.

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