Charles Oliver, 44, is charged with assaulting the five women at his home in Woodstock between November 2011 and the early part of 2013, the Chicago Tribune reported Tuesday.
Some items found in the search of Oliver's home do not belong to the alleged victims already identified, said Sgt. Charles Amati of the Woodstock police.
Police charge Oliver met the women through personal ads posted on the Craigslist website.
He would meet them elsewhere and take them to his home.
One woman said she was locked in the basement, while another said he tied her to a chair.
Oliver was free on bail after being arrested on Jan. 28 for assaulting two women when he was re-arrested Feb. 24 and charged with attacking three more women.
Prosecutors have said they will seek to have his bail revoked while he awaits trial.