GREENBELT, Md. (WJZ) — A Chevy Chase man who secretly videotaped children in his home is sentenced to 20 years in federal prison Tuesday.

Jonathan Mark Oldale, 55, of Chevy Chase, Md., was sentenced to 20 years, followed by a lifetime supervised release, on charges of production and possession of child pornography.

Oldale would secretly film children using hidden cameras in the bathrooms of his home.

Oldale must also register as a sex offender anywhere he lives, works or is a student, under the Sex Offender Registration and Notification Act (SORNA).

In addition, Oldale must pay a $400,000 money judgment in lieu of forfeiture of Oldale’s interest in his residence, which Oldale used to facilitate his crimes.

According to his plea agreement, on May 5, 2017, Montgomery County Police got a complaint from an employee at a children’s gymnastics facility in Silver Spring that Oldale had placed a backpack containing a camera disguised to look like a car key fob in a bathroom at the facility.

The employee also told the officers about an incident before when Oldale had left a backpack in the same bathroom.

Oldale’s home was searched where police found three laptop computers that had installations of browsers used to access the “dark web” and some files that had were titled consistent to child pornography.

Videos recorded in the bathrooms show the cameras were placed under the sink or in a basket in the shower, and multiple cameras were in a bathroom.

The videos depict minor children changing in and out of bathing suits, taking showers and using the toilet.

Children were invited to “splash parties” at Oldale’s home in June and July 2017, with emailed invitations sent to their parents. Oldale would encourage children to change their clothes or take showers before they went home.

Of around 79 children who appear in the videos, around 52 are seen nude at some point..

USB drives revealed Oldale store videos that included lists of the children’s names followed by a description of the swimsuit worn by the child.

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