This from Eric Haak:

Chicago had a still and box Monday in an auto repair shop at 31st and Kostner.  It was putting up a lot of heavy black smoke but was under control fairly quick.  The first image was taken 15 minutes in.  Once Tower Ladder 54 was put to work, things darkened down real quick.
fire trucks at fire scene in Chicago

Eric Haak photo

firemen with hose line at fire scene

Eric Haak photo

Chicago FD Engine 99

Eric Haak photo

fireman o roof with smoke

Eric Haak photo

fireman o roof with smoke

Eric Haak photo

firemen with hose line at fire scene

Eric Haak photo

firemen at fire scene

Eric Haak photo