ST. LOUIS – A former high school security guard who videotaped his repeated sexual abuse of a child was sentenced to 25 years in prison.

Mark A. Bennett, 48, pleaded guilty in U.S. Federal Court in St. Louis to a charge of the production of child pornography.

Bennett worked at McCluer North High School in the Ferguson-Florissant School District but did not meet the victim through his job.

Bennett pleaded guilty in March and admitted the victim was less than 10 years old when he began abusing her and filming the abuse.

Investigators found 589 pictures of videos of the girl’s abuse, as well as 1,500 files containing child sexual abuse material, according to Bennett’s plea agreement.