Oak Lawn officials are on alert after sharp screws were found burrowed into playground equipment at a popular park in the Chicago suburb earlier this month.
The screws were discovered at Memorial Park, but the objects were spotted and repaired before anyone was injured.
"The screws were screwed into the slide and knocked off the heads to create a nice sharp edge," Oak Lawn Parks Superintendent Joel Craig said. "It's extremely disheartening and disturbing."
A total of 10 drywall screws were found mounted in the middle of two plastic slides and purposely engineered to cause injury at the end of a run when a child is most unsuspecting and vulnerable, authorities said.
A mother, who didn't want her name to be used, said she's been especially careful since finding out about the vandalism.
"The first thing I do before I let her go down a slide or go on any equipment is take a look to make sure there's nothing she can get hurt with," she said.
Police stepped up patrols in the area and the equipment is being checked every day.
No suspects have been identified.
In March, a 2-year-old child was injured after a dozen razor blades were found glued to playground equipment at a park in East Moline, Illinois.