The Bergen County Arson Squad is investigating a large fire that occurred Saturday evening at Washington School in Lyndhurst.

Authorities say the flames broke out in a classroom just after 6 p.m. Heavy smoke was spotted coming from the basement and fire crews from several towns responded to the scene.

Crews had had zero visibility while combating the flames, according to authorities.

The fire department says that the Board of Education will provide more information about the start of school next week.