A still-burning fire that tore through 2800 hectares of scrub has cost Fire and Emergency NZ more than $7 million to fight.

The blaze, which started in Waiharara in the Far North on December 18, twice forced the evacuation of the seaside village of Kaimaumau and has been described as one of the most complex in New Zealand’s history.

Firefighters scaled down their operations at the site in February, but said the fire could continue to burn in peat for another six months.

A costs breakdown released this week under the Official Information Act showed Fire and Emergency NZ had spent $7,023,231 on controlling and suppressing the blaze.

READ MORE: * Far North fire: Large area of blaze contained as response team downscales * 'Lots of work to be done' as devastating fire still burns in Far North * Far North fire: Villagers will spend third night evacuated from swamp blaze

That included costs that had been invoiced up to March 22.

“It is possible that total costs may increase as additional invoices are received,” Nicky Chilton, a director at the office of Fire and Emergency’s chief executive, wrote.

“Please note that the invoices represent the additional cost we incur beyond our fixed cost of maintaining a response capability.”

Of the money spent, the bulk – $4.48 million – went on hiring aerial services, such as helicopters.

The next biggest cost was external firefighting services, at $1.22 million.

That included resources belonging to, and people employed by, other agencies, Chilton said.

Examples given were forestry company and Department of Conservation personnel, as well as digger, bulldozer and water tanker operators.

Employee payments, which included overtime and travel reimbursements, came in at $335,293.

Volunteer payments, such as reimbursements for mileage, petrol, and meals, totalled $237,547.

More than $130,000 was spent on firefighting foam.

The Pigeon Valley fire of 2019 – thought to be the most destructive blaze in the past 60 years – cost Fire and Emergency $11.8 million to fight, while the Lake Ōhau wildfire in 2020 cost $1.3 million.

At its peak, more than 100 firefighters were battling the Waiharara blaze.

Department of Conservation national fire manager Aroha Hughes said it could take 10 to 15 years for the ecosystem to recover from the fire.

It burnt through a scientific reserve which was home to endangered plants, fish, lizards and birds including a rare sun orchid, the black mudfish, the Northland green gecko and the Australasian bittern (matuku).

An official cause of the blaze has not been released.