Firefighters are being contaminated at the scene of a building fire in Glendene, where asbestos was discovered.

Firefighters tackling a blaze at a large indoor sports arena have discovered asbestos burning in the building's roof.

The fire at Arena 149 - an indoor field for those who play the shooting game airsoft - on Hepburn Rd in Glendene, West Auckland, was reported at 6.09 am on Friday, Fire and Emergency NZ shift manager Dallas Ramsay confirmed.

A crew from Glen Eden found a significant fire on the upper floor upon arrival. Further crews arrived to a thick pool of black smoke coming from the building, Counties Manukau area assistant commander John Booth told Stuff at the scene.

RYAN ANDERSON/STUFF Firefighters needed to keep the roof wet to prevent spread of asbestos dust.

There were 12 crews, with more than 60 firefighters at the scene at the height of the blaze. No-one was reported inside the building, Ramsay said.

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Booth said the fire had torn through 60 per cent of the building, before firefighters managed to contain it to a section of the upper floor. The fire was out by 7.30am.

RYAN ANDERSON/STUFF The fire damaged about 60 per cent of the building, Counties Manukau area assistant manager John Booth said.

Two crews will be on standby at the scene for the rest of the day, as per standard procedure, Henderson senior station officer Geoff Gardner said.

The building's structural support beams had been "severely damaged" he said, meaning there was a risk the roof could collapse.

The blaze had also caused the second storey floor to go soft and holes had begun to appear in it.

RYAN ANDERSON/STUFF Firefighters have contained the fire to a section of the upper floor.

Firefighters were being decontaminated as the roof contained asbestos, meaning the roof would have to be kept wet to keep it from blowing away.

Auckland Council's pollution control team visited the building and found no other issues besides the asbestos, Gardner said.

If inhaled, asbestos particles may cause coughing and phlegm. Asbestos is a proven carcinogen, which can cause cancer after prolonged exposure to large amounts of it.

Ryan Anderson/Stuff At the height of the fire, 60 firefighters were at the scene.

An Auckland Council spokeswoman confirmed the Council's Environmental Health team had attended the fire to assess and monitor any asbestos associated risk.

"There are currently no concerns that any asbestos has left the site, however asbestos air monitoring has been arranged."

A council officer would remain on site to monitor the situation and assist the fire service with their investigations.

Ryan Anderson/Stuff Fire and Emergency NZ vehicles lined Hepburn Rd, shutting it down to motorists.

Following investigations, the asbestos will need to be removed as per WorkSafe New Zealand's code of practice, the spokeswoman said.

FENZ vehicles, including a canteen, breathing apparatus and command station had shut down much of Hepburn Rd by 7.40am.

Houses opposite the fire were not evacuated, however Hepburn Rd remains closed.

Ryan Anderson/Stuff Homes opposite the fire had not been evacuated.

St John Ambulance attended the fire, however no-one was injured.

"Please avoid the area to allow crews to work safely," the West Harbour Volunteer Fire Brigade wrote on social media.​

The cause of the fire is not yet known but fire investigators would go inside the building once it is safe to do so, Booth said.

Supplied/Nikki Baker Firefighters instructed buses to use another route as Hepburn Rd was blocked.

A Hepburn Rd resident said he saw a fire truck outside his house and woke his son and daughter up, thinking firefighters were there to give out lollies for Christmas.



But when he saw the hose on the street he realised there was a fire.



A family can be seen watching the scene from their front deck and two people have emerged onto the footpath to talk about the fire.

Nikki Baker took a photo of the smoke as she stood waiting for her bus at the corner of Hepburn Rd and Barrys Rd about 500 metres away.

"The local bus had to reverse back down the road to go another route as firefighters had said we couldn't go further down Hepburn road."