Police are investigating the cause of a fire at a public school in the Lake Macquarie area this morning.

About 12.30am (Friday 6 February), fire crews were called to the school on Secret Corner Road in Rathmines after reports a one of the buildings was well-alight.

When crews arrived they found the hall and canteen ablaze but managed to contain the fire.

The fire has been extinguished and investigators are expected to examine the scene later today.

The cause of the fire has not been established.