POLK COUNTY, Fla. (WFLA) — A 53-year-old Polk County teacher’s assistant was arrested Tuesday after authorities said he inappropriately touched a student and asked for her nude photo.

According to the Polk County Sheriff’s Office, detectives with the Special Victims Unit began investigating Roberto Diaz, 53, on Feb. 20 after an 18-year-old student came forward with sexual offense allegations.

Diaz works as a 9th-grade teacher’s assistant and Bible studies teacher for Poinciana Christian Preparatory School South.

Deputies said the student told school staff that Diaz had sent her about six messages between Feb. 6 and Feb. 14 asking for a nude photo of herself via the WhatsApp messaging app.

After the victim refused Diaz’s requests and told Diaz to stop sending her messages, Diaz placed his hand on her chin and neck area and attempted to kiss her and touch her breast, deputies said.

School officials alerted the Polk County Sheriff’s Office and immediately suspended Diaz pending an investigation. He was later fired.

During an interview with detectives, deputies said Diaz admitted to inappropriately touching the student against her will. He also admitted to asking her for a nude photo of herself.

“It infuriates me that someone in this kind of a position, as an educator, role model, a religious instructor, and a person of influence, would attempt to take advantage of a student for his own sexual satisfaction,” Polk County Sheriff Grady Judd said. “He should be locked up in prison and never have access to schools or children again.”

Diaz was charged with one count of sex offense on a student by an authority figure.