A well-known Islamic religious leader in Texas has been busted for sexually assaulting four children — though authorities believe he’s victimized countless others.

NY Post (h/t Thereza B) Mohamed Omar Ali, a 59-year-old Somali national, was arrested Friday on charges of sexual assault of a child and sexual indecency of a child after an investigation was launched in September, Fort Bend County Sheriff Troy Nehls Mohamed Omar Ali, a 59-year-old Somali national, was arrested Friday on charges of sexual assault of a child and sexual indecency of a child after an investigation was launched in September, Fort Bend County Sheriff Troy Nehls told reporters at a press conference Monday

Nehls described Ali as a popular “religious leader” who spent time at several mosques in Fort Bend County, as well as in greater Houston. Investigators believe Ali also victimized other children dating back to 2013 after he arrived in the US.

“We do know that there are other victims out there,” Nehls said. “And it is our plea today to those victims to please reach out to us so we can conduct further investigation.”

Ali met his alleged victims through their parents, who invited him into their homes and paid him to teach their children the Quran, Detective Michael Alexander said. All of Ali’s purported victims were juveniles at the time of the alleged abuse, according to Alexander, who declined to specify whether they were boys or girls.