The shooting took place at about 8:13 p.m. in the 9200-block of South Commercial Avenue.
Police said the woman was in a vehicle at the intersection when she was wounded in the back. That's when police say the woman drove to 7th Ward Alderman Greg Mitchell's office...where she met first responders at 95th Street and Merrion Avenue.
The woman was transported to the University of Chicago Medical Center in serious condition, police said.
Video from the scene shows evidence technicians examining the woman's jeep with bullet holes in the windshield in the alderman's parking lot.
Police said no one is in custody. Area Two detectives are investigating.
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