Troopers responded about 2:45 p.m. to the eastbound Interstate 290 ramp to Homan Avenue for a reported shooting, police said.
Two people were shot in the Homan Square incident, police said.
One person was able to get to a local hospital, and the other was transported via ambulance.
RELATED: Chicago shooting: 14-year-old boy shot in West Garfield Park, police say
The exit ramp is closed while troopers investigate, police said at about 3:30 p.m.
Anyone with information on the shooting is asked to call state police at 847-294-4400, or email ISP.CrimeTips@Illinois.gov. Witnesses can remain anonymous.
INTERACTIVE SAFETY TRACKER | Track crime and safety in your neighborhood