A Maryland elementary school substitute teacher and coach arrested on child pornography charges has been ordered to remain in jail pending trial, according to prosecutors.

Christopher H. Speights, 34, appeared Friday in Prince George’s County District Court for his bail review hearing one day after Maryland State Police said they seized more than 150 graphic images and videos of children performing sexually explicit acts on devices he owned.

Speights has taught and coached at Bradbury Heights Elementary School in the Capitol Heights area for nine years, according to court files. Officials with Prince George’s County Public Schools said he no longer works for the system.

None of the photos appear to depict students from Bradbury Heights, said Gina Ford, a spokeswoman for the Prince George’s County State’s Attorney’s Office.

Detectives launched an investigation into Speights after they were alerted to the exchange of child pornography through a Dropbox account connected to him, Maryland State Police said in court charging papers.