Frank Licka, 19, was found Tuesday around 12:45 p.m., after collapsing while mowing grass at Union Creek Park.
Licka died of multiple injuries and his death has been ruled an accident, according to the Cook County Medical Examiner's office.
Bystanders immediately summoned emergency medical services and attended to the victim pending arrival of paramedics, according to a statement from the Frankfort Square Park District.
He was taken to Franciscan St. James in Olympia Fields, where he was pronounced dead at 1:44 p.m. Police do not believe foul play was involved, said Tinley Park Police Chief Steve Neubauer.
Licka was a 2013 graduate of Lincoln-Way North High School, and a freshman at Bradley University in Peoria. He had worked for the park district during his high school years.
"Frank Licka was a valued employee of the Frankfort Square Park District and a dear friend and colleague to many," according to a statement from the park district.
"The Park District extends its sorrow and deepest sympathy to the family and friends of Frank."
This story is developing. Check back for more.
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