MOKENA (CBS) — An Aurora man has been charged with aggravated criminal sexual abuse of a child after Mokena police discovered them in a car parked at Buske Park, police said.

Steven Sly, 21, of 2140 Lilac Lane, was charged Wednesday after the 13-year-old Mokena girl told police they had sexual intercourse, Mokena Police Cmdr. Dan Rankovich said.

The two had known each other for several months, he said.

A Mokena police officer was on routine patrol through the park, 11435 W. Hillside Lane, when he checked on Sly’s parked car, Rankovich said.

Sly reportedly told police he thought the girl was 16 years old