The shooting took place at about 10:02 p.m. in the 6200-block of DuSable Lake Shore Drive near the Reggie's On The Beach restaurant.
Police said a 14-year-old girl and two men, ages 30 and 31, were struck by gunfire.
A gunman fled the scene on a bicycle after opening fire, police said.
The girl was shot twice in the leg and was transported to Comer Children's Hospital in fair condition, police said.
The 30-year-old man was shot in the leg and the 31-year-old man was shot in the back, with both victims transported to the University of Chicago Medical Center, where they were listed in fair condition, police said.
Late Monday night, there was a large presence near the 63rd Street Beach where the shooting occurred.
Officers focused their investigation in a parking lot where a private party was reportedly taking place.
Detectives have not offered any motive or what might have led up to the shooting.
No one is in custody and Area One detectives are investigating.
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