Police are warning CTA riders after three robberies on trains in which a man rips necklaces off female passengers before fleeing through open doors. View Full Caption Chicago Police Department

CHICAGO — Police are warning CTA riders after three robberies on trains in which a man rips necklaces off female passengers before fleeing through open doors.

Police said the suspect identifies female passengers wearing necklaces and swipes the jewelry as the train approaches a stop.

The crimes have taken place in the 800 block of West Harrison Street (UIC-Halsted Blue Line) at 3:30 p.m. on July 27; in the 100 block of West Cermak Road (Cermak-Chinatown Red Line) at 7:05 a.m. on Aug. 3; and in the 1200 block of North Milwaukee Avenue (Division Blue Line) at 6:50 a.m. on Aug. 12.

Police describe the suspect as a bald black man with a dark complexion between 5 feet, 3 inches and 5 feet, 6 inches and between 145-155 pounds.

If you have information, contact police at 312-747-8384.

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