A man who was struck by a steel roller coaster at an Ohio theme park last week after he entered a restricted area to retrieve his lost keys has died from his injuries. Kings Island theme park near Cincinnati has said Arntanaro Nelson entered a fenced area there Wednesday night. The 38-year-old Wilmington man was found on the ground with a “critical injury” and died Friday at a hospital. The Hamilton County coroner’s office has listed Nelson’s death as a “suspected accident,” but it remains under investigation. His death was announced on Monday.