A fire at the former Mataura paper mill in Southland, where hazardous material is stored, has been extinguished.
Emergency services were called to the blaze on Kana St at around 1.40pm today.
Traffic was diverted around Mataura and significant delays were expected, police warned.
More than 30 firefighters were on-site to battle the blaze, which was inside the hydro generator in the building, a Fire and Emergency NZ spokesperson confirmed.
Hazardous ouvea premix is stored on the floor above, around 30 metres away from the fire.
Ouvea premix is a hazardous substance which releases toxic ammonia gases when wet.
It's a waste product from an old aluminum smelter and was abandoned at the paper mill when the company contracted to deal with the waste went into liquidation.
The blaze was extinguished this afternoon after the power generator was shut off.
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