SAN MATEO (CBS SF) – Uniformed and plainclothes police officers were patrolling the grounds of a San Mateo high school Thursday morning in light of a threat that was made to the school through a social media site this week.

A female student at Aragon High School notified school administrators Wednesday morning about the threat, made on an anonymous “confessions” page she created online, San Mateo Unified High School District Associate Superintendent Kirk Black said.

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School staff notified the district, which in turn alerted San Mateo police, Black said.

The threat, described as “rambling,” specifically mentioned Thursday’s date, and some parents have elected to keep their students home for the day, but Black said he doesn’t expect a large dip in attendance.

Thursday’s attendance figures for Aragon were not immediately available Thursday morning.

Black said administrators have been in contact with parents and have ensured them that the threat has “very little credibility” to it.

“We have to consider it and use an abundance of caution,” Black said.

Officers were on the campus at the start of the school day, along with school administrators and counselors, and students were monitored as they entered the school, Black said.

As a precaution, a private security firm conducted surveillance at the campus overnight, he said.

San Mateo police Sgt. Dave Norris said officers will be at the school for the duration of the day, but would not disclose how many.

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Police detectives were continuing to investigate the case, but have not identified a suspect, Norris said.

Black said the student who reported the threat had created the “confessions” page on the Google doc for Aragon students, and copy-and-pasted posts onto a Facebook page she created.

The student told administrators that posts were coming in so rapidly, she hadn’t noticed the threat until it was already on the Facebook page, Black said.

She has since removed the post from the page, he said.

San Mateo police officers and detectives went to the school, located at 900 Alameda De las Pulgas, immediately after getting word of the threat, according to Norris.

The district normally has one student resource officer for its seven high schools, Black said.

The San Mateo-Foster City School District was also notified of the threat, as one of its schools, Baywood Elementary School at 600 Alameda De Las Pulgas, is just a few blocks away, Norris said.

Anyone with information about the threat is asked to call San Mateo police at (650) 522-7700.


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