HARRISBURG, IL (KFVS) - A police investigation is under way at the Harrisburg Unit 3 School District.
According to Superintendent Michael Gauch, the district was alerted of a building issue at the middle school around 10 p.m. on Tuesday.
Gauch said Illinois State Police was called in to sweep through all of the Harrisburg schools.
ISP investigators did not get on scene until 3:30 a.m.
The district called off class on Wednesday to give investigators enough time to do a thorough search.
Gauch said the district is erring on the side of safety.
Classes will resume as normal on Thursday.