Police said the robbery happened on a CTA Blue Line train at 117 West Lake Street around 9 p.m.
The violin, valued at $10,000, was inside a black storage case and has a distinct wood grain finish on the back, police said. It does not have a serial number, since it was custom-made.
The suspect is described as a 30-40-year-old man who is between 5-foot-8 and 5-foot-11. He wore a black jacket with white striped sleeves, black pants and white gym shoes.
Police asked anyone with information to call them at 312-745-4447 or submit an anonymous tip at CPDTIP.com and use reference RD#JJ-214845.
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