The shooting happened around 3:32 a.m. in the 200-block of South Campbell Avenue near Jackson in the Near West Side neighborhood, Chicago police said.
A group of people was standing outside when shots were fired.
The girl was inside a parked vehicle when she was shot in the abdomen and taken to the hospital, where she later died.
The victim has been identified as Reign Ware by the Cook County Medical Examiner's Office.
Note: The medical examiner initially provided a different name for the victim.
A man, 24, was shot in the thigh and taken to the hospital in good condition.
Alderman Walter Burnett of the 27th Ward told ABC7 the girl was with her parents when she was shot and killed. Her father was the man who was also injured after by hit twice by the gunfire, and he was taken to Stroger Hospital.
Bullet-riddled homes and cars showed the chaos that erupted overnight.
"I heard one shot, then 30, 40 more shots," a witness, who wanted to remain anonymous, told ABC7. "They've been partying over there for the last week, just chilling. Ain't heard one shot. I don't know what went wrong."
The witness saw everything unfold from his bedroom window. He said he saw at least four men hop out of a car in what looked to be a targeted ambush.
"Drive-by, pull up, get out... drive-by is when you keep going," the witness said. "'We're getting one of these people when you get out and start shooting. Somebody was in the car and got the baby out. The baby was limp. It wasn't no life in her. So, they got the baby out and ran down there and got into another vehicle and went to the hospital."
Ald. Burnett said the girl's father was standing outside of a vehicle when he was shot.
A candle sat where the deadly shooting unfolded, happening during the Memorial Day weekend, which is typically marked with violence. The 5-year-old victim is the youngest shooting victim so far this weekend, according to Chicago police crime data.
READ MORE | Chicago shootings: At least 25 shot, 5 killed in Memorial Day weekend violence across city, CPD says
"How you going to go through saying I killed a baby? An innocent baby," the witness said.
A community activist is offering a $1,000 for any information leading to an arrest and conviction. A motive behind the shooting is under investigation.
No one in custody. No other injuries were reported.
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