More than 100 firefighters extinguished flames inside the basement of Hicksville High School Monday evening after a blaze broke out in the furnace.

Fire officials say the fire was accidental and began when an oil burner in the basement ruptured around 6:30 p.m. Students are on vacation this week, though authorities say there were some students inside the building working on a robotics project for a future competition. Everyone inside made it out safely.

Firefighters reported no damage to any of the classrooms. Fire officials say they turned the power inside the school off until the 500 gallons of spilled oil is properly cleaned up. According to authorities, there is extensive damage to the heating, electric and plumbing systems. The district says it will attempt to repair the school while students are gone for the break.

One firefighter was hospitalized with minor back and neck injuries.