Chicago police said the robbery happened on the sidewalk in the Bucktown neighborhood's 1900 block of West Armitage Avenue just before 6:30 p.m.
A United States Postal Inspection Service public information officer confirmed the victim is a mail carrier who was on her route in the neighborhood at the time.
A suspect, identified only as male, took property from the mail carrier, a 53-year-old woman, before fleeing southbound on Wolcott Avenue, police said.
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The USPIS public information officer said the mail carrier was not injured.
Area Five detectives are investigating. Further information was not immediately available.
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