ST. LOUIS – A former substitute teacher in the St. Louis area who was charged with rape died in the St. Louis County Justice Center.

Brandon Holbrook was found dead in his jail cell Monday, September 26. He was alone in the cell under quarantine when he was found unresponsive. An autopsy is pending. Holbrook is the third inmate to die at the St. Louis County Justice Center.

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Prosecutors charged Brandon Holbrook, 30, with three counts of statutory rape and six counts of statutory sodomy.

Authorities received a report earlier this month of an inappropriate relationship between Holbrook and a 14-year-old victim. Investigators learned he was a substitute teacher at Bernard Middle School when he initially met the victim.

According to court documents, investigators believe Holbrook was grooming the victim through social media platforms around May 2022, exchanging messages and photos with the victim. The suspect went to the home of the victim and engaged in sexual acts on at least three separate occasions, per court documents.

Holbrook previously served a substitute teacher around St. Louis County, including the Mehlville School District.