Two teenage girls in Maryland allegedly tortured a 16-year-old boy who has a mental disability. Police say they filmed the incident on their cell phones, according to multiple sources.

Lauren Bush, 17, of Mechanicsville in St. Mary's County, and an unnamed 15-year-old accomplice, allegedly stabbed the boy, kicked him in the groin, forced him to perform sexual acts with an animal and made him walk across a frozen pond, Chesapeake Today reports. When the boy fell through the ice, the teens did not help him.

The 16-year-old victim, who was not identified, is said to have an intellectual disability. WJLA-TV reports that he has autism, but that report is unconfirmed.

The St. Mary's Count Sheriff's Office could not be reached for comment.

“His vulnerabilities made this crime more heinous,” St. Mary's Sheriff Tim Cameron said, according to SoMdNews. Cameron added that the alleged offenses were among the most disturbing crimes he's ever seen.

Both girls are students at Chopticon High School in Morganza and were said to have known the boy prior to the crimes, which occurred between December and early February, SoMdNews notes.