LAFAYETTE (CBS SF) — Police have lifted a lockdown at Acalanes High School in Lafayette and have detained a suspect they say was involved in the incident.

The suspect was detained off of the school’s campus, according to Lafayette police.

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The high school was put on lockdown Friday morning after school officials became aware of threats posted on social media, according Contra Costa County Sheriff’s Office spokesman Jimmy Lee.

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Investigators searched the school for any possible threats and determined the school was safe, police said.

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