Convicted sex offender arrested in Joliet, Illinois for taking photos of boys at swimming pool

A convicted sex offender in Joliet, Illinois has been charged with taking photos of boys at a swimming pool.

Police said 61-year-old Farrell Theis was working his job to restock vending machines at the Joliet Park District building at 3000 W. Jefferson St. shortly before 9 a.m. on Feb. 2, when a staff member caught him taking pictures of high school boys using the swimming pool.

Detectives learned Theis is a convicted child sex offender, and found the photos of the boys on his cell phone.

Theis was arrested on Tuesday in Romeoville on a charge of child photography by sex offender.

It's not clear how Theis got authorization to be on park district property as a convicted sex offender.

Court information for Theis was not immediately available.