PACIFIC PALISADES (CBSLA.com) — A threat against Palisades Charter High School has made a comeback on social media, but many parents are taking no chances and are planning to keep their kids home Tuesday.

Investigators say they saw the threat against the high school in Pacific Palisades first circulated months ago. But it seems to have picked up again with the start of school year.

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The threat warns students to not go to school because an expelled student made “threats about ‘shooting up the school,'” according to an email sent to parents by school administrators.

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The school sent a note to parents Monday night about receiving the threat, and say they immediately contacted police and interrogated the student, who is currently in a “45-day interim placement.”

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Police say that while they are not taking the threat seriously, they plan to have extra patrols on campus anyway.