NAPERVILLE, Illinois - Naperville North High School shut down on Wednesday after someone emailed the school a bomb threat.
A backpack that had been placed near a door was checked out by the bomb squad.
Naperville District 203 officials sent an email to parents to keep their kids at home.
Police blocked all of the parking entrances with squad cars. After they discovered the backpack, the perimeter was expanded and Ogden Avenue was shut down. The bomb squad used bomb-sniffing dogs and no explosives were found.
All after-school activities have been canceled.
All students and staff were removed and are safe..
The students were brought to Naperville Central High School so parents could pick them up.
Police searched the 500,000 square foot building and grounds and cleared the scene just before noon. They said a threat to children at school is a serious offense. They are working with the FBI to determine the origin of the email threat.