Thick, acrid, smoke has spread for kilometres from a massive scrap-metal fire raging in South Auckland, and the fire is expected to burn until at least tonight.
Fresh fire crews have taken over at Sims Pacific Metals in Favona where 1600 tonnes of car parts, roofs and tyres are ablaze.
More than 80 firefighters and 20 fire engines are tackling the out-of-control blaze at James Fletcher Drive, in Favona, which broke out about 2am.
The crews are also struggling to ensure there is enough water to fight the blaze, and are also using an excavator to break up the materials fuelling the flames.
A witness said the flames were "as high as the warehouses around it".
About 1600 tonnes of scrap metal, including old car parts, roofing, vinyl and tyres, covering an area of 100m by 70m and 12m high, are providing plenty of fuel for the fire.
Thick, dark-grey smoke has been billowing out over the surrounding area all morning, raising health concerns.
Chet Nich, who lives about 3.5km away in Mangere, said the "acrid smell of plastic smoke woke me at about 4am".
"I searched my house to check it wasn't on fire.
"I closed all my windows but it was still bad, headache material.
"At first light I saw it was a large cloud from the East Mangere area.
"The stink had only just cleared from my house at 10.20am. I did consider leaving home for the morning to avoid the smoke."
Reece NZ's Auckland distribution centre operations manager Howard Diprose said even from 5km away he could see dark-grey smoke.
"It burns your lungs. You can't breathe it in. It doesn't sting, but it feels quite gritty on the back of your throat. It is obviously not good for your health.
"It smells like somebody is burning plastic rubbish. It is very strong."
His firm has had to close all of the doors and windows to keep the smoke out.
"I feel sorry for those a lot closer to it."
A cordon is in place around the fire, and only a trickle of workers have made it through.
At least 25 people are waiting outside the Kaka St cordon, unable to get to work. Some people have given up and left.
One worker who made it through down the road from the scrap yard said there was a "stench of rubber in the air".
Fire and Emergency New Zealand area commander Geoff Purcell said the "deep-seated" fire could burn all day.
"It's a huge fire and there's a lot of really thick, black smoke coming from it.
"We are doing everything we can to get this fire under control, and our crews are working extremely hard."
Crews who have been tackling the blaze overnight are being swapped out with fresh crews who will work throughout the day.
Excavators and heavy machinery will soon be used to help break up the scrap metal pile to help put it out.
Firefighters have been using water to try to dampen the flames.
"Making sure there's sufficient water, given the scale of the fire, has been a challenge," Purcell said.
Purcell said people should avoid the area if they can and close their windows and doors off from the smoke.
There were no hazardous substances or chemicals involved in the fire.
"We understand that this will cause disruption in South Auckland, and we want to assure people that our firefighters are giving 100 per cent to getting it under control."
As yet the cause of the fire was unknown. There have been no reports of injuries.
"Before the cars were shredded they were drained of fuels and oils, but there are still some minor explosions going off, in tanks, bits and pieces within scrap heap," Assistant area commander Auckland City Barry Fox said.
Trudy Burt could see large amounts of black smoke from the Otahuhu rail bridge.
"I hope everyone got out OK – how terrible.
"I can see the red of the flames as high as the surrounding warehouses."
Witness John Caldwell said the smoke was "toxic".
"It is affecting breathing. The fire department won't advise if it is or not."
Another witness said the pile of scrap metal was about 12m high. "It is a huge fire - too hot to stand around.
"I could feel the heat from about 100m away."
James Fletcher Drive is closed between Savill Drive and Kaka St.
Sims Pacific Metals told Newstalk ZB it wouldn't comment about the inferno.
The Companies Office lists one New Zealand director, Hamish McBeath, and three Australian directors for Sims Pacific Metals Limited.
Fletcher Steel owns half of the company.