LAPEER, Mich. (WWJ/AP) – Authorities say two teenagers are facing charges in connection with threats of violence at Michigan middle school made in text messages.

The Flint Journal reports the 14- and 15-year-old students were charged this week under the state’s anti-terrorism act with making a terroristic threat, using a computer to commit a crime and conspiracy to commit terrorism.

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The charges come after authorities say one of the students sent text messages to a friend threatening to commit “mass murder” at Zemmer Middle School in Lapeer County’s Mayfield Township. It’s unclear how the second student was allegedly involved.

Sheriff’s investigators were able to identify the teens, who have not been named publicly due to their age. They’re being held without bond until a Feb. 28 hearing.

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Startled parents took to social media to voice concerns after they were greeted by a police presence while dropping of their kids on Tuesday. A little later that morning they received a text message alerting them to the threat, adding that it was “being dealt with” and that those responsible were not in school.

Posting on Facebook, one student’s mother wrote, “(It) would have been nice if the school let us know ahead of time and gave us the choice to send our kids or keep them home.”

The Lapeer Community Schools district has said visible police presence at the school was meant “to ensure all students and staff feel safe.”

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