Two emails including threats with racial phrases and extremely graphic images were sent to more than 5,000 people in the Gardner School District, authorities say.
The pair of messages, both sent from district vendor “plusportals.com,” went out to students and parents early Saturday morning.
Police were alerted to the first around 12:35 a.m., which included “threats against a school” and racial phrases, Sgt. Jeffrey LaBonte of the Gardner Police Department said in a statement Saturday afternoon.
The second detailed that the threatened incident would occur on Jan. 24, and contained graphic images that seemed to be downloaded from the internet, according to police.
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Gardner police said they checked the schools and have not identified any threat.
In a post on Facebook, Gardner High School acknowledged and apologized for the incident, and noted they are working with Gardner police to figure out the origin of the message.
Police say they Gardner’s technology department to investigate the incident, which is an active criminal investigation.
PlusPortals is billed by Rediker Software, a company based in Hampden, Massachusetts, as a solution to “support online learning and create a seamless connection between your school, students and their families.”