Naperville police said Wednesday afternoon that they responded to a bomb threat, but no explosives were found. Police searched the building with area bomb squad personnel and bomb dogs.
The school asked that all students remain at home Wednesday morning. Students who had already arrived at school were picked up at Naperville Central High School, officials said.
Officials said the school day and all activities have been canceled to allow Naperville police to investigate the threat.
Chopper 7HD flew above the school as some Naperville police squad cars patrolled the area.
Further details on the nature of the threat against the school were not immediately available.