A Hillsborough County teacher accused of placing hidden cameras in the changing area of a fashion design class at Bloomingdale Senior High School had allegedly been doing so since 2017, according to a new document.

According to the Hillsborough County Sheriff’s Office, on Tuesday, Sept. 11, a student entered a designated fitting/changing room within a fashion design classroom to try on clothing. While changing into various outfits, the victim noticed an electronic recording device set up to secretly record the same area where she was undressing.

According to the sheriff’s office, the student immediately dressed herself and reported the incident to the school administration.

The administration began an initial investigation and alerted HCSO. Detectives began a criminal investigation and learned that the cameras had been secretly placed in the changing room.

The sheriff’s office says Ackett told detectives that he placed them there intentionally and for the purposes of recording the victim in various stages of undress. Ackett admitted to detectives he was recording students while they were changing.

According to a search warrant obtained by News Channel 8 on Thursday, “During a post Miranda interview with Mark Ackett, he admitted to owning the cellular phones described in the warrant, placing them in the changing room of his classroom and having done so to secretly record his students disrobing since 2017.”

Ackett no longer works at the school. The school district says he resigned.

Ackett started his employment with the school district in 1991. He worked in the school district’s central office before he became a teacher at Bloomingdale High School in January of 2017.