STRATHAM, N.H. (CBS) – A New Hampshire middle school was placed in lockdown on Monday after a student found a shotgun shell inside a locker room.

Stratham Cooperative Middle School in Stratham, N.H., was placed in lockdown at 11:35 a.m. when a student found the shell on the floor of the boys locker room and alerted a teacher.

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With the school in lockdown, the principal, assistant principals and school resource officer investigated to determine if there was any additional threat, officials said.

After a preliminary search, administrators and police then decided to put a secure campus lockdown into place. By doing so, students were able to continue with regular school activities while the investigation continued.

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Students who needed to move around the school were escorted by staff members.

After interviewing multiple students and searching lockers in the building, investigators determined around 1:25 p.m. there was no threat. The lockdown was lifted at 1:25 p.m.

“We are so proud of the students, staff and police department in their quick response and collaborative effort to ensure the safety of our campus community,” principal Bill Furbush said in a statement.

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