CPD said the incident took place about 3:40 p.m. Tuesday, as a 14-year-old girl was walking near North Long and West Pensacola avenues in Portage Park.
A man who was initially standing behind the garage at 5356 W. Cullom Ave. tried to engage her in conversation before blocking her path, Chicago police said.
The girl did not respond, and ran to Portage Park Elementary School.
The man ran after her, police said.
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She reached a crowd of parents outside the school and lost sight of the man.
The suspect is described as a man between the ages of 38 and 48; 5-feet, 8-inches to 5-feet, 10-inches tall; and having a round face, slight beard, short dark hair with a receding hairline, black jacket, black work boots and professional camera hanging from a neck strap, police said.
Anyone with information is asked to call Area Five detectives at (312) 746-6554.
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