"Officers and detectives are currently on scene beginning an investigation," police said.
Officials told WLS-TV they received multiple calls around 2:30 a.m., and that officers arriving at a house discovered three people who had been shot.
The three people were then transported to an area hospital, where one of them later died. Two other people later walked unassisted into an area hospital.
Aurora police told WLS-TV the four injured have non-life-threatening injuries.
Officials have not disclosed details about a suspect, only saying that additional information will be released shortly.