The robbery happened Wednesday around 3:36 p.m. at the Red Line Belmont stop at 945 W. Belmont Avenue in Lakeview, according to police.
Detectives say the victim was on the train when robbed by the offenders, Mass Transit detectives said.
No injuries were reported. It is unknown what the suspects took.
Anyone with information is asked to contact police at (312) 745-4706.
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