Authorities said other parks in the town had been checked and were clear, but they will continue to be checked by both patrol and plainclothes officers on every shift.
On their Facebook page, police have asked parents to check equipment before letting children play, and said older, unescorted children should be warned as well.
Police credited maintenance personnel for discovering the vandalism. No injuries were reported.
A week ago, authorities in western Illinois found a dozen razor blades glued to playground equipment in a city park in East Moline.
Illinois officials said a 2-year-old was cut by one of the blades while playing, but was not seriously injured.
No suspects have been found in either case.