Authorities discovered the wounded man underneath the CTA ‘L’ tracks, about half a block south of Waveland Avenue, between Sheffield and Wilton, around 8:55 p.m.
The victim, described by police as a white male, was bleeding profusely from the head.
The man was bleeding so badly, a responding officer asked dispatch to “put a rush on an ambulance.”
"There's a lot of blood here," said the officer.
As of 9:20 p.m., it was still unclear what caused the man’s injuries.