A multi-vehicle accident snagged the outbound Stevenson Expressway southwest of downtown Chicago Thursday afternoon.

Only one lane was open at 5 p.m. on the outbound Stevenson (I-55) at Halsted Street, just past the Dan Ryan Expressway (I-90/94) merge.

Ramps from both directors of the Dan Ryan feed and merge onto the outbound Stevenson, making for traffic jams in multiple directions.

Information about the crash was not immediately confirmed. But at least six vehicles were involved, and first responders from the Chicago Fire Department were on the scene.

Illinois State Police were also on the scene, as were Chicago police — who were looking in the green space on the roadway for something someone may have thrown over.