CHICAGO (CBS) — After first postponing the start of the school day due to a threat against the school, Naperville North High School has now closed for the day.

“Naperville North High School will be closed for the entire day today, Wednesday, September 22, to allow the Naperville Police Department to further investigate a threat made against the school. Staff and students will not have access to the building while the police conduct their investigation and search of the facility,” District 203 said in a Facebook post.

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The school district earlier told students to stay away from the school, and said students and staff who had already gone to school before learning of the threat were being moved to a safe location.

Students who had already gone to school are now being reunited with their parents at Naperville Central High School.

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“Parents can begin to pick-up students at Naperville Central High School at 10:00 a.m. Parents should enter NCHS parking lot off of Hillside by the Auditorium at the far west end of the building. All parents should remain in their vehicles for the entire reunification process. Parents must show staff their ID and will be asked the name of their student. Students will be called by our staff to exit the building and will be directed to their parent’s vehicle,” the district said in a message on the school’s website.

After-school activities also have been canceled for the day, and social-emotional support will be provided at Naperville Central for students who want to speak to a social worker.

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No further information was immediately available.

CBS 2 Chicago Staff