LANCASTER (CBSLA) – A 15-year-old boy was arrested Monday on allegations he posted a social media threat against Highland High School in Lancaster.

The teen was arrested at his Lancaster home Monday night by Los Angeles County Sheriff’s deputies on felony criminal threat charges.

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An unnamed 15-year-old boy following his arrest on allegations of making a criminal threat against Highland High School. Nov. 11, 2019. (LASD)

The boy is not a student at Highland High, the sheriff’s department confirmed, but attends a different Lancaster school. He was not identified because he is a juvenile.

The nature of the threat was not confirmed, although the sheriff’s department described it as a “joke.”

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The Antelope Valley Union School District told CBS2 that it learned of the threat Monday night and then notified the sheriff’s department.

The school is operating on a normal schedule Tuesday, with no cancellations to classes.

The boy is being held at the Eastlake Juvenile Hall on no bail.

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“Our investigations have shown that a large majority of these threats are made by students as a ‘joke’ or ‘prank,’ however our deputies MUST treat every threat as real,” the sheriff’s department said in a statement Tuesday. “Regardless of their intention, these threats are unlawful, carry serious criminal consequences and it is important our children know that.”