Lincoln High School parents received a letter from the principal on Tuesday informing them about a social media post that warned students to stay away from school on Wednesday.
Montgomery Middle School students received a similar notice on Wednesday, and on Thursday an almost identical threat hit San Diego High School.
“That doesn't surprise me,” said Tim Ware, coordinator for school safety and security with the San Diego County Office of Education.
Ware says many times after school shootings, copycat behavior can follow for weeks if not months.
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"I know and [have] heard from colleagues up and down the state and around the country that this is the typical cycle,” said Ware.
But Janelle Battaglia with the San Diego Center for Children says there are other contributing factors.
"We're just seeing an overall increase in mental health issues after children are coming back into school," said Battaglia. "So that makes sense that across the board, there's just an increase in problems.”
Battaglia says her staff has reported an increase in aggression and misbehavior among the students they serve.
"Youth have not been around each other so those important social skills that they developed by being in school have been absent for quite some time," Battaglia explained.
The threats come as the U.S. Surgeon General issued a rare public health advisory this week about the mental health crisis facing our youth.
"Unfortunately, it comes as no surprise to those of us who have been working in children's mental health," said Battaglia. "Even prior to the pandemic, but especially during this current pandemic, we've certainly seen an increase.”
In these difficult times, Battaglia says the best thing you can do is be there for your children.
"Really try to focus on quality over quantity, in terms of spending time with your child," said Battaglia. "And again, don't ignore the signs. So please reach out if you're feeling concerned about anything.”
All threats reported in San Diego schools this week were unsubstantiated, according to police.