Police searched the student's home and did not find any weapons. They believe that "the student had no real intent to carry out a shooting," the release states, but will send the case to the Santa Clara County District Attorney's Office and Juvenile Probation Department for review for criminal charges.

Police Sgt. Craig Lee said that the student was not arrested but was placed on a 5150 hold, an involuntary 72-hour psychiatric hospitalization for people who are believed to be a danger to themselves or others. The student's gender has not been identified.

Around 6 p.m. on Thursday, police noticed comments on the police department's Instagram page, posted by a user with a profile that had no identifying information on it, stating that the person was going to "shoot up" Gunn. Detectives and school resource officers worked to identify the commenter and by 8:40 p.m. contacted the student at home in Palo Alto and took the student into custody for a mental health evaluation, according to a news release issued early Friday.

A school resource officer, the district's interim safety manager and extra counseling staff will be at Gunn on Friday, and all teachers and staff will be "extra attentive to concerns or needs," Hendricks said.

Gunn Principal Kathie Laurence notified students families in a message early Friday morning before school started, writing that "we continue to work on building a positive school culture at Gunn as we know that it has a direct relationship on wellness and safety."

"The incident was handled very quickly and collaboratively between the Palo Alto Police Department and the Palo Alto Unified School District," she told the Weekly Friday morning. "We were all set to go into the school day today knowing the situation had been resolved and everybody was safe to come to school."

"Unfounded threats such as this one are not only criminal in nature, but can also create a great deal of stress and anxiety for students, parents, school staff, and the community in general," police said. "As always, we encourage anyone who sees something suspicious, be it in person or online, to promptly report it to their local law enforcement agency."

Anyone with information about this incident is asked to call the department's 24-hour dispatch center at 650-329-2413. Anonymous tips can be emailed to [email protected] or sent by text message or voicemail to 650-383-8984. Tips can also be submitted anonymously through the police's free mobile app, downloadable at bit.ly/PAPD-AppStore or bit.ly/PAPD-GooglePlay .

This week's incident "exemplifies why we have put very designated focus into this topic," Hendricks said. "We want to be prepared. We want to have our partnerships in place with law enforcement and community agencies. We want our sites and district to be fully repaired to receive information ... and respond in the best possible manner."

Improving school safety is a high-level focus of the district's this year, with plans to add cameras and make other changes to secure campuses against active shooters and other emergencies. The Board of Education approved on Tuesday funding for two new district positions to oversee and implement security and emergency response procedures across all schools.

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Gunn High student who made alleged school shooting threat taken into custody

Police believe teen's comments, left on Instagram, were unfounded