The incident happened in Putnam County just after 10:15 a.m. on Wednesday, Oct. 2, when authorities responded to a lockdown alarm activation at Mahopac High School that indicated it was "not a drill," according to the Carmel Police Department.
As a result of the alarm, both Mahopac Middle and the Mahopac Falls schools were also put into lockdown.
Officers from Carmel Police and the Putnam County Sheriff's Office quickly arrived at the high school, as well as those who had already been responding to a scheduled lockdown drill at the nearby Austin Road Elementary School.
Once there, authorities quickly realized that an electronic notification related to the Austin Road School's lockdown drill had been erroneously broadcast to Mahopac High School, causing the high school administrative staff to start a lockdown according to protocol.
Because the Middle and Mahopac Falls Schools are on the same campus, they also began their own lockdowns, police added.
All three schools were cleared without incident by 11 a.m., and an investigation confirmed the erroneous notification and lockdown, according to Carmel Police.
No threat or danger to any of the schools was found.
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