Highland Park High School was dismissed early Thursday after a threatening note was found on campus for the second straight day.
Officials with the district told NBC 5 that a note was found in the boys bathroom Wednesday and another in the same spot on Thursday.
Specifics regarding the threat have not been revealed, though officials said they do not believe there is an imminent threat.
As a precaution, the school dismissed students early at 2:40 p.m. and allowed police to search the building. Normal dismissal time is 3:30 p.m.
No devices were found.
In an email to parents, the district said they would continue to monitor the campus closely and asked parents to talk with their children about how seriously threats, written or otherwise, are taken on campus.
Some University Park police were still at the school Thursday night and double-checking the premises. No civilians were allowed into the school Thursday night.
NBC 5's Deanna Dewberry, Randy McIlwain and Alex Russell contributed to this report.