The inbound lanes of the Stevenson Expressway were closed early Wednesday evening near Pulaski Road for a shooting investigation, officials said.
The closure affects I-55 northbound between Pulaski Road and Kedzie Avenue, with drivers encouraged to seek alternate routes.
According to Total Traffic Chicago, the closure has caused solid traffic back-ups stretching south to the I-55/I-294 interchange, and was prompted by a shooting investigation.
One person was wounded in the shooting and later transported to an area hospital where their condition is unknown, according to Illinois State Police.
There was no further information available.