Firefighting is expected to continue on Matakana Island for several days.

The blaze, which broke out on Saturday night, has already burnt through more than 37 hectares of scrub and pine slash.

It was contained on Sunday night but 30 firefighters and three helicopters continue to work through to keep it under control with fire breaks.

Fire and Emergency incident controller Jeff Maunder says thermal imaging from last night’s drone flights has identified around 200 hotspots that would have to be dealt with.

Helicopters are helping combat the hotspots identified in the fireground. Photo: Supplied.

All of the hotspots are inside the containment lines that were established on Sunday, he says.

"Ground crews and helicopters were back on the job this morning.

"Firefighters will be using handtools to dig out hotspots and expose any fire burning underground, then soaking the area with water to ensure it is completely cool.

"The work is complicated by the large number of dangerous trees, damaged or weakened by the fire."

Crews worked through the night to make sure the fire didn't flare up. Photo: Fire and Emergency New Zealand.

Jeff says the fireground remains off-limits to the public.

"Fire and Emergency is arranging additional crews and equipment to continue the operation for the next several days to ensure that the fire won’t reignite, before the fireground is handed back to the landowner."

Monsoon buckets being filled with water to use on the Matakana fireground. Photo: Supplied.