A person lighting a camp fire is believed to be the cause of a fire which has destroyed a prestigious piece of Raglan coastline.
And days after the fire began on Wednesday night, firefighters remain at the scene, now on foot, trudging through dangerous terrain to put out hot spots.
Deputy principal rural fire officer Matt Cook said the intensity of the fire proved just how susceptible some areas of the country still were to fire, despite regular rainfall over the past couple of weeks.
The fire started small but was whipped up in strong winds to end up more than 500m long and 100m wide.
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Two helicopters were called in on Thursday morning and stayed at the scene until dusk, Cook said.
Firefighter crews were still there today, dampening down all deep-seated hot spots, a mission that could only be completed by foot.
The fire began near an area popular with mountain bikers and walkers, but Cook said it had remained relatively unscathed.
He said the cause of the fire was accidental as there was evidence at the site of someone having lit a fire while camping or picnicking.
Who was responsible remains unknown.
He said areas of coastline, despite the rainfall it might receive, were still vulnerable to fires.
The fire was not only taking up valuable Fenz resources but also came at a cost to ratepayers who would be footing the bill.
The Waikato fire district, which stretches from Coromandel to Mokau, went into an open fire season last week.
Given the volatility of some areas, he urged people to hold off lighting any fires until after the country had been through the alert level process.
"Yes it's an open season but if they can refrain from burning we would appreciate that."