The posts were shared in Western Massachusetts from another municipality in another state, according to the Springfield Police Department.
The individuals who shared them locally are the subject of a criminal investigation, said the Springfield Police.
There will be an additional police presence at the school, which is reportedly Springfield Central High School, on Monday, Oct. 25 out of an abundance of caution, the department added.
Springfield Police Commissioner Cheryl Clapprood said the department is aware of the threat and has been actively investigating since Friday, Oct. 22, to find the source.
"This weekend, Springfield Public Schools has been working with officials in following up with an anonymous Snapchat post threatening harm against a Central High School," the Springfield School District said in a statement on Facebook.
"Please be advised of official reports that the threat was made against a school with that name in a different state. Media reports and law enforcement advisories indicate that the Snapchat post caused concern for schools named Central High School nationwide.
"Despite this information, SPS will ensure increased safety measures in and around Central High School here in Springfield out of an abundance of caution."
If you have any information on who is responsible for these posts please call the Detective Bureau at 413-787-6355 or anonymously Text-A-Tip. Text CRIMES (2-7-4-6-3-7), type SOLVE, and your tip.
“I want to reassure everyone that our detectives are working diligently to determine where this post originated and find out who is responsible, Clapprood said. "We have a successful track record of identifying individuals making social media threats utilizing various resources to track down those responsible. We take every threat seriously and investigate them thoroughly. In the meantime, we will have a heightened police presence at the schools as this investigation continues.
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