Dirigo High School in Dixfield was locked down Monday and a person who was walking past the school with what looked like a gun was detained by police, according to authorities.

The person detained was a 17-year-old who was not in school because of “administrative action” by school officials, said Jeffrey Howe, Dixfield’s police chief.

The teenager was walking past the school with an Airsoft gun, which shoots plastic pellets, Howe said. Howe said gun looks real but isn’t illegal and doesn’t require a permit to purchase. It’s commonly used in war games, similar to paintball.

Howe said the school went on lockdown and police were called after the teenager displayed the gun. The manner in which the Airsoft was displayed it isn’t clear, he said.

Howe sent officers to the teen’s home and he was questioned by police at the station for about two hours. No charges were filed, Howe said, but the incident is still under investigation.

No one was injured.

The school was locked down for about 90 minutes in the incident, which began shortly after 11 a.m.

School Superintendent Deborah Alden said the school held a brief assembly after the lockdown to tell students what had occurred and then resumed a normal class schedule.