A Thursday autopsy couldn't immediately identify what killed a man whose body was found on a Chicago Transit Authority bus on Wednesday night.
Further tests were needed to determine how Robert Pearson died, an official with the Cook County Medical Examiner's Office said.
Pearson, in his 40s, was found aboard a bus when it stopped near the 1100 block of South Kedzie Avenue, in the west side Lawndale neighborhood, an official said.
He was pronounced dead at 9:47 p.m.
CTA officials did not return calls for comment.