A Hudson Valley school was placed on lockdown around the same time another nearby school district was put into a hold in place.

On Thursday, Sullivan West High School has been placed on lockdown as police investigated a social media threat.

Also on Thursday, several Robert J. Kaiser Middle School students were involved in an altercation. Two Monticello students engaged in increasingly threatening behavior towards each other and later staff members, school officials say.

Staff tried to calm things verbally, but a safety staff member had to place a student in a hold when the student became physically aggressive, officials say.

One safety staff member was injured.

“Our staff is routinely trained using the Handle With Care Behavioral Management guidelines which emphasize verbal de-escalation tactics,” Principal Nick Millas said. “Unfortunately, physical holds are necessary when a student is posing an immediate threat to himself or to others. In the rare cases that a student is placed in a physical hold, our staff is taught to do so using methods that minimize the risk of injury to either the staff or student. Student and staff safety is always our top priority.”

For the remainder of the school day, the school was in a hold in place. During the hold in place, students were only allowed to leave their classrooms if escorted by an adult.

The incident was unrelated to a reported social media threat and subsequent lockout at the Sullivan West School, officials say.

The threat at Sullivan West was later found to be “not credible," according to the Monticello School District.

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