PLEASANT HILL (CBS SF) — A 13-year-old student allegedly planned a mass shooting for Thursday at Valley View Middle School in Pleasant Hill, police said today.

The FBI notified Concord police at about 6 p.m. Friday about a message on social media that was shared between two students of the middle school at 181 Viking Drive.

Concord police told Pleasant Hill police that the message was allegedly about a planned mass shooting on the last day of school, which is Thursday.

Pleasant Hill and Concord police officers served a search warrant at a Martinez home and seized several guns and arrested a Valley View student.

The student was taken to Contra Costa County Juvenile Hall on suspicion of terrorist threats.

On Facebook, Valley View Principal Lisa Sullivan said out of an abundance of caution, “We will add supervision on campus as well as provide counseling if needed to help ensure students and staff feel safe.

“This has been a difficult year as schools around the nation have been receiving threats daily. We take every threat very seriously.”

Pleasant Hill police urged anyone with information about the incident to contact the department.

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