2 appliances are on scene off Puckpool Hill, where crews are working externally to extinguish the fire that has taken hold of a building near the site’s main entrance.
Firefighters are using 2 hose reel jets and a main jet to tackle the flames and water is now being pulled from a nearby hydrant to continue the firefighting efforts.
It is understood the building is empty and abandoned.
The alarm was raised by members of the public at around 17:10.
UPDATE @ 18:00 – Police are now in attendance amid the suspicious circumstances of the fire.
Fire crews on the ground are continuing to dowse the flames and are swiftly gaining control of the blaze. They are using a thermal imaging camera to identify the remaining areas of intense heat.
UPDATE @ 18:18 – Station Manager Jeff Walls has told Island Echo that the area affected is around 10m x 10m.
He has confirmed that the fire is being treated as suspicious and the fire service are working alongside their Hampshire Constabulary colleagues.
Site caretakers have been called to Harcourt Sands and are expected to continue dealing with the matter once firefighters have damped down and left the scene.