A free DJ-led concert at Daley Plaza in Chicago was cut short June 26th when a fight broke out among dozens of people, police said.
Authorities arrested 10 adults and nine juveniles, according to the Chicago Sun-Times, and all were charged with mob action, which is a misdemeanor.
Two teenagers with head injuries were reportedly listed in stable condition.
Police did not know why the fight broke out at press time.
The concert, part of the Nomadic DJ series featuring