By Selena Hernandez, CBS 11 News

PLANO (CBSDFW.COM) – Holiday break has started a day early for students at Plano East Senior High School. The campus was shut down on Tuesday morning after some serious threats were received by school officials, and nobody wants to take any chances.

School administrators said that all classes had been canceled because of two different bomb threats. The principal of Plano East Senior High School, Karen McDonald, does not believe that the threats are credible, however, neither she nor district officials are willing to gamble on that guess.

Instead of the regular classes, the Plano Independent School District will do a thorough sweep of the entire campus with canine units and bomb squad officers. Meanwhile, the district is working with the Plano Police Department to follow up on leads and find the person or persons responsible for the bomb threats.

A 17-year-old Plano East Senior High School student has been arrested in connection with this case. Police said that he scribbled the first threatening note and left it on a bathroom wall on Friday. Police searched the campus, but did not find anything suspicious. The student has not been identified, but police said that he faces a charge of making a terroristic threat.

The second bomb threat came on Monday, also from a note found on a wall. Police do not believe that the two threats are related, but the Monday threat is ultimately what led to the school’s closure on Tuesday. “This was just extra caution because of two in a row,” said Lesley Range-Stanton, a school district spokeswoman.

According to the school district, students will not be required to make up this missed day later in the school year.

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