Police responded just before 2:30 a.m. to reports of the shooting in the 700 block of South 5th Street, according to Aurora police. Three adults were found with gunshot wounds and taken to an area hospital.
Booker, 20, was pronounced dead about a half-hour later, according to police and the Kane County coroner's office. He lived in Montgomery.
The two other adults were stabilized, police said.
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Shortly after, two more people arrived at Copley Medical Center with gunshot wounds from the same incident, police said. They were also stabilized.
The investigation is in its early stages, police said, but detectives believe this was not a random attack and is an isolated incident.
"If you saw something, we need you to say something," Fichtel said. "No matter how small the information might seem, we need to people to come forward with any bit of information about what happened early this morning."
Anyone with information is asked to call Aurora Police's Investigations Division at 630-256-5500, or give information anonymously through Crime Stoppers at 630-892-1000. Crime Stoppers is offering a cash reward up to $5,000 and anonymity to citizens who offer information leading to the arrest of the fugitives.
The Chicago Sun-Times contributed to this report.