Investigators are confident that a hot car exhaust started a sulphur fire at a fertiliser plant in Napier overnight.
Photo: Google Maps
Emergency services were alerted to the blaze at Ravensdown in Awatoto, just after 2am today.
Ravensdown chief executive Greg Campbell described the situation as "unusual", saying that a car came off the road and through the plant's fence before starting a fire.
"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," he said.
No one was injured and police are now working to determine how the car got into the property.
Campbell said the fire was minor and there was no structural damage to the plant, which 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 the visibility on the road.
Photo: Google Maps
Wanoa said by the time more fire crews arrived, they found that the fire was "well involved".
"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The fire was brought under control at around 5:40am and crews were withdrawn from the scene.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 this morning to determine the cause of the fire.
It is not the first time the Ravesndown plant in Napier has caught fire.
In 2016, firefighters had to battle a blaze which also involved sulphur.
Firefighters feared a possible explosion while battling the fire on 1 December 2016.
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 had to be 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 because of the toxic gases.