Police are looking for the attacker who plunged a sharp object into the chest and shoulder of a 26-year-old man, critically injuring him early Wednesday in West Ridge.
The man was discovered along the 6200 block of North Oakley Avenue at 1:22 a.m., Chicago police said.
He was taken to Saint Francis Hospital in Evanston, where he was listed in critical conditiion, police said.
Area 3 detectives are investigating.