It happened on 92nd Street at Manchester. We're told there was a driver and passenger in the rig traveling on the South Loop. A bus passing them on the freeway motioned that the rig had a problem on the underside.
The truck got off the freeway, and when the driver put on the brakes, it caused more heat, spreading fire to the motor.
Both occupants were able to get out of the big rig. We don't have any information at this point about any injuries. The cargo did not catch fire.