On July 8, a 63-year-old man was beat up and robbed while on a train in the 100-block of Congress Parkway in Downtown Chicago, police said.
On Tuesday, police arrested four underage people in relation to the crime in the 7000-block of Cottage Grove Avenue.
Each juvenile is facing a felony count for robbery to a victim over 60 and a felony count for aggravated battery.
Police arrested an 11-year-old girl, 14-year-old boy, 15-year-old girl and a 16-year-old boy. CPD did not release their names.
No other information was available.
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