Police said the alleged assault happened in the Humbodlt Park neighborhood's 3000-block of West Augusta Boulevard on Aug. 12 around 2:25 p.m.
Police released a photo of the suspect, who allegedly approached a 10-year-old girl and touched her inappropriately.
The suspect is described as a man between 55 and 60 years old who weighs 150-170 pounds. He was last seen with short gray hair, and he was wearing brown shorts, a pink T-shirt, brown sunglasses, and brown sandals.
The suspect also carried a black bag and rode a black bicycle.
Police asked anyone with information to contact the Special Investigations Unit at 312-492-3810 or submit an anonymous tip at CPDTIP.com and use reference RD # JK370440.
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