A car crashing through a fence and bursting into flames is believed to be the cause of a sulphur fire at a fertiliser plant in Napier.
Emergency services were alerted to the blaze at Ravensdown in Awatoto shortly after 2am on Sunday.
Ravensdown chief executive Greg Campbell described the incident as "an unusual one" and said the company was working with police.
"It looks like a car has left the road and actually come through the fence to our plant and has somehow caught on fire. So we don't know how or why that has occurred. Obviously, the police are conducting an investigation. The fire was put out by the fire brigade. Nobody was injured, very minor damage," he said.
"I think the car catching on fire actually caused a small sulphur fire."
He said the fire was minor, caused no structural damage and the plant would open for business as usual on Monday.
Fire and Emergency NZ said when the first two crews arrived, they found a fire on the ground floor of the five-storey building.
FENZ Central Communications shift manager Mike Wanoa said at the same time, State Highway 51 had to be shut for traffic management as smoke was impacting visibility on the road.
By the time more fire crews arrived, they found the blaze was "well involved", Wanoa said.
"It had extended to the sulphur products and to the ceiling of the building," he said.
Nine fire trucks responded to the blaze, as well as a command unit.
The fire was brought under control at around 5:40am and crews were withdrawn from the scene.
Wanoa said the police and a fire investigator are now combing through the site on Sunday morning to determine the cause of the blaze.
It is not the first time the Ravesndown plant in Napier has caught fire.
On December 1, 2016, firefighters battled a blaze also involving sulphur, fearing a possible explosion.
A fire broke out on a conveyor belt suspended over as much as 1000 tonnes of sulphur in a storage shed at the plant.
It took 60 firefighters wearing breathing apparatus to bring it under control.
At the time, Area Commander Ken Cooper told RNZ the burning sulphur was difficult to extinguish.
"If you disturb it with water it goes into a sort of powder and dust and you can get a dust explosion," he said.
Two firefighters were treated at the scene after getting sulphur dioxide, a highly toxic gas, in their eyes.
The gas is produced when water comes into contact with the sulphur.
In the rural Awatoto area downwind, five houses had to be evacuated due to the toxic gases.
RNZ
