Authorities are investigating a fire that broke out at Nesconset Elementary School in Smithtown on Thursday night.
Suffolk County police officers and local firefighters responded to the scene on Gibbs Pond Road at 7:31 p.m.
A police spokeswoman said the fire broke out in a modular classroom facing the inner courtyard of the school.
Smithtown, Nesconset and St. James fire department firefighters extinguished the flames.
There were no reported injuries.
Arson Squad detectives are investigating the cause of the fire.
Smithtown School District officials were not immediately available for comment.
