The crash happened on Saturday at about 8:34 p.m. in the 2800-block of E. 77th Street in the South Shore neighborhood, police said.
Police said the 15-year-old was on a scooter when she was struck by a vehicle that fled the scene.
She was later found lying on the street; she was taken to the University of Chicago Hospital where she died. She was identified as Violet D. Harris by the Cook County Medical Examiner's Office.
Chicago police said a 13-year-old girl was also hurt in the crash and was taken to a hospital in good condition.
Police have not yet released a description of the vehicle involved.
The motorized scooter remained in the middle of the street Saturday night as crash reconstruction investigators tried to gather what evidence they could from the hit-and-run crash that killed 15-year-old Violet Harris and injured her 13-year-old companion.
"Getting ready to cross the street and next thing you know a speeding black sedan just kept going and hit her, and kept riding," violence interrupter Justin Peters said.
A violence interrupter at Chitown Crime Chasers, Peters is speaking on behalf of the family. The tragedy is hitting particularly close to home.
"Violet is the niece of one of my team members, and it's very devastating," Peters said. "It's hitting the whole family, all of us is hurting right now."
A freshman and honor student at Hyde Park Academy, Harris is described as someone who filled any room she walked into with smiles, bringing joy to those she came into contact with.
"This was a child who had her whole life left," said Cassandra Chatman with Chitown Crime Chasers. "So I'm hoping the person that the person that did it will come forward or someone saw it will come forward."
No other information was immediately released. Chicago police are investigating.
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