Scrap yard fire still burning in Mangere

A fire at a south Auckland scrap yard is still burning more than 16 hours after it began.

Emergency services were called to Sims Pacific Metals on James Fletcher Dr in Favona, Mangere, just before 2am on Wednesday morning. 

Eighty firefighters tended to the fire armed with 3km of hose. Those on the scene said it would take them "a wee while" to get the blaze under control. 

"The scrap metal pile's about 2000 tonnes of scrap metal. That includes vehicles, fridges, roofing iron, all sorts of scrap steel and materials in that pile."

The cars had been drained of fuel but there were still explosions as water failed to penetrate the thick pile of metal.

The blaze is just smaller than Eden Park, and is taking a "huge demand" on the fire service's resources across Auckland.

Smoke continued to belch across south Auckland throughout the day, forcing some factories to close. Public health officials visited the area and advised people to keep doors and windows closed. 

Truck drivers waiting to make deliveries had orders to sit tight a kilometre from the fire site, causing significant delays. 

Firefighters have yet to pinpoint the cause but say nobody was on site when the blaze began.