A massive blaze which destroyed a $2.6 million home near Kerikeri is being treated as arson.
Fire broke out at the five-bedroom, 500sq m Ness Rd home just before midnight on Friday and was so fierce firefighters could see the glow from 8km away.
Owners Chris and Alison Robinson were in Hamilton at the time.
The English migrants bought the property in 2005 and converted it into five-star accommodation, Killara Luxury Lodge.
It had been for sale for $2.6m but the couple withdrew it from the market this year when they became convinced they were being poisoned by 2,4,5-T used to control gorse or dumped in the area in the 1960s.
Mr Robinson would not comment on the fire yesterday, saying he did not want any publicity.
Northland fire investigator Craig Bain said the cause of the blaze was still under investigation, and samples taken from the remains of the building had been sent away for analysis.
The fire's starting point had been traced to a room on the ground floor.
Kerikeri police Senior Sergeant Peter Robinson - no relation - said yesterday the fire was being treated as arson.
The man in charge of the investigation, Detective Sergeant Sam Bindon of the Kerikeri CIB, would say only that police were continuing their investigation and had yet to establish the cause of the blaze.
He would not comment on reports that a rock was thrown through a window at the lodge a week before the fire.
Via their "100 per cent Deadly NZ" blog at www.dioxin-nz.com, the Robinsons say they are taking the Government to court for misleading them with its 100 per cent Pure campaign. The country's pollution-free image had convinced them to sell their property in France and move to New Zealand, they said.
They are claiming about $20m in damages, which includes money they lost when they could not sell their property and the cost of future cancer treatment.
They are also suing the real-estate agent and the lawyer who sold them the property, and have laid complaints over alleged inaction against the Northland District Health Board and the Northland Regional Council.
With the lodge apparently closed - the website was shut down some time ago - Mrs Robinson had been running a dog-grooming business from the property.
Firefighters were hampered on Friday night by a chained gate and a lack of water. They spent more than six hours at the scene, returning on Saturday morning after a re-ignition.
It was the biggest property fire in the Far North since the Kerikeri High School blaze of June 2010.