Fire and Emergency say there is "more steam than smoke" coming from the site of a fire at a metal recycling plant in the Auckland suburb of Papakura on Thursday morning.
It is understood to be at the Global Metal Solutions site on Hunua Road, which had previously caught fire in January and March 2021.
Speaking to Morning Report on Thursday, Manurewa-Papakura Ward councillor Angela Dalton said this was "not [Global Metal Solutions's] first rodeo".
"Papakura residents - quite rightly - will be wanting some answers to the question as to how this continues to happen."
In a statement, Global Metal Solutions managing director Craig Tuhoro said the cause was still being determined.
He said the business had experienced a "flame-up incident" while cleaning the yard.
"Most importantly, our people are safe. Their wellbeing is our top priority, and we are taking this matter seriously."
Tuhoro said Global Metal Solutions would resume operations soon "continuing our commitment to responsible metal recycling and waste separation, constantly improving our processes to enhance safety, efficiency, and environmental outcomes".
Fire and Emergency assistant commander Chris Delfos told Morning Report there has been a "worldwide trend" of fires in recycling places.
"I don't want to jump to any conclusions yet, but often it's caused by lithium-ion batteries that are thrown away with recycled material."
Delfos said Fire and Emergency would be working with Global Metal Solutions to see what it could do to prevent future fires.
Earlier, Assistant Commander Katie Pocock said there were seven fire appliances including three aerials still in action.
The fire is now contained, and under control, but not yet out.
Pocock said the firefighters have been working diligently on the deep-seated burning in piles of metal waste up to 10 metres high overnight.
She added the piles were being pulled apart by heavy machinery.
Thick, black smoke billowed from the fire when it broke out at about 4.30pm on Wednesday, with an emergency mobile alert later issued.
Emergency alert send to phones in the area. Photo: RNZ
Pocock said there was now "more steam than smoke" coming from the site due to the amount of water firefighters were using.
She confirmed the warning for people to stay inside and avoid exposure to smoke was no longer in force.
The scene at the fire on Wednesday. Photo: RNZ / Lucy Xia
Hunua Road remains partially closed on Thursday morning.
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