Michael Gargiulo is accused of killing 18-year-old Tricia Pacaccio of Glenview.
Gargiulo currently lives in California where he is charged with killing two women and the attempted murder of another.
The Chicago Sun-Times reports that a California police detective says Gargiulo indicated that he had killed others.
A spokesperson for Cook County State's Attorney Anita Alvarez called the officer's comment "inflammatory and misleading."
