A Serra High School freshman was arrested Wednesday on suspicion of scrawling a threat about a school shooting in a restroom at the Tierrasanta campus.
The suspect — whose name, age and gender were withheld — told school investigators the menacing comments, discovered on Tuesday, were "not meant to be taken seriously," and authorities do not believe the threat was credible, according to San Diego Unified School District officials.
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Still, school police decided that the message met the criteria for classification as a criminal threat, SDUSD spokeswoman Maureen Magee said.
The threatening graffiti made reference to a shooting that supposedly was due to take place following the school's spring break, which is next week, according to Magee.
At least 19 threats have been made against San Diego-area schools since last month's massacre at Marjory Stoneman Douglas High School in Parkland, Florida, and prosecutors have charged nine juveniles in connection with the incidents, according to the San Diego County District Attorney's Office.
On Friday, school and city officials plan to hold a news conference outlining the ramifications of the spate of school threats, punishments faced by those who issue them and efforts to discourage youths from engaging in such offenses.