A pair of teenagers have been arrested over a fire at a school at Raymond Terrace overnight.
Emergency services were called to Irrawang Public School on Greer Street just after 10:30pm with reports of a fire, when they arrived, officers found two demountables alight.
Fire and Rescue NSW crews attended and extinguished the blaze, which destroyed the buildings and an inspection of other buildings found a number of classrooms had been broken into and vandalised.
Two teenage boys, aged 14 and 15, have been arrested and taken to Raymond Terrace Police Station were they remain.
A crime scene has been established and will be examined by specialist forensic officers.
Inquiries continue.