Please note the video in the player above is from a previous report from the Tuesday bomb threats.
The Aurora Police Department said three libraries in the western suburb were evacuated as a precaution due to threats posted online, in an incident similar to reported threats at Chicago-area libraries earlier this week.
Thursday's set of threats also included a report of an active shooter at one of the libraries, but they have all since been determined to be false, police said.
Aurora police later issued a notice giving an all clear to the three public library locations.
Police continue to investigate the threats from both days, police said.
On Tuesday, police were also called to libraries in Aurora, Evanston, Addison and Schaumburg. Those libraries were also evacuated as a precaution.
Another threat was called into the Harold Washington Library in Chicago Thursday. Police swept the building, and it was not evacuated.
Authorities did not say whether the threats are connected.