CHICAGO (STMW) — Two people have been charged with assault, for allegedly threatening and punching an 11-year-old girl who would not give them her souvenir beach ball Sunday night downtown near the Lollapalooza music festival.

A 45-year-old woman and her daughter were walking along the 0-100 block of East Jackson Boulevard just before 9 p.m. Sunday, when the two men approached and an argument ensued over the souvenir beach balls the victims were carrying, police News Affairs Officer Jose Estrada said.

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One of the men verbally threatened the victims if they did not turn over the balls, and the other man struck the girl in the stomach, Estrada said.

The victims flagged down a passing Chicago Police vehicle and the men were arrested, Estrada said.

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Conrad Slimak, 19, of the 1100 block of North Lake Shore Drive, was charged with misdemeanor counts of battery, assault and intoxication by a minor, Estrada said. The second man, who refused to give his name or address to police, was charged with misdemeanor assault.

Both are expected back in court on Aug. 29, according to police.

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Area Central detectives are investigating.