According to Montgomery County Regional Dispatch, Westbrooke Village Elementary School in Trotwood was put on lockdown Monday morning following reports of an unidentified individual entering the structure.
Around 9:30 a.m., the incident was reported at the Westford Road school.
A few pupils were inside at the time, according to the authorities.
The building is being searched by police for the person.
The name of the individual involved has not been verified, and no injuries have been recorded.
As a precaution, the lockdown is still in place while the inquiry is ongoing.