CHICAGO (WBBM) — Police say a teenager was arrested after a group of at least 20 people attacked someone on Michigan Avenue on Saturday night.

Police said a 15-year-old male is charged with felony mob action. A police spokesman said the teenager beat someone at about 8:30 p.m. Saturday on the 800 block of North Michigan Avenue, in front of Water Tower Place.

LISTEN: Newsradio 780’s Steve Miller reports

Police said an officer saw what looked like several people – at least 20 – jumping up and down and, when the officer got closer, he saw that they were beating someone.

Police said the 15-year-old is the only one charged in the attack. All the others fled the scene.

Police said the victim refused medical treatment and refused to prosecute for the attack.

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