The incident happened on Monday, Sept. 16, when a lockdown alarm went off at Horace Greeley High School in Chappaqua, New Castle Police said around 11:45 a.m.
After officers investigated the incident, they eventually determined that it was an unknown alarm malfunction.
The department is now continuing the investigation to determine the circumstances of what triggered the alarm, police added.
This is a developing story. Check back to Daily Voice for updates.
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