The posts' origin is still being investigated, but many districts are now taking precautions, especially in the wake of the deadly school shooting in Michigan.
It is a horrifying situation for kids in which history keeps repeating itself, and on Thursday, Nassau County police, Homeland Security, and school officials outlined the latest threat of school violence playing out on TikTok.
The chatter surrounds December 17, which is being called "Shoot Up Your School Day."
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Police Commission Patrick Ryder said the threat is not credible, but it is a drain on their resources.
"'All schools in the United states will be targeted on December 17th. Stay safe. Stay home.' That's gone viral," he said. "We are going to be out there tomorrow visiting every one of our schools."
In Nassau County, that includes 450 buildings -- with fewer cops then able to investigate crime.
Additionally, another trend playing out are posts and reposts of stock photos of guns that come with crafted phony threats.
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"And understand, a 12-year-old girl took to the internet and sent something out that shut a school district down for three days," Ryder said.
Nassau police say they are dealing with a significant spike in school threats this year, up 148% from last year and 25% from 2019.
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