Multiple fires broke out across Auckland on Tuesday night with fireworks believed to be at blame.
Pictures supplied to Newshub show Mt Wellington enveloped in smoke and flame.
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At its peak the blaze measured 200 metres by 100 metres and needed multiple crews in place to battle it.
Seven appliances and a water tanker were called to the mountain just before 10pm.
"Quite a lot of our resources in Auckland were dedicated to fighting that," said Fire and Emergency NZ principal advisor Peter Gallagher.
The fire sent smoke billowing across the city but by 12:10am firefighters had the blaze under control.
Separate crews were called out to a second fire on Mt Eden just after 10pm. Five trucks were called to the site to extinguish the fire.
Gallagher told The AM Show FENZ received 88 fireworks related call outs across New Zealand in the last 24 hours
Two more fires broke out in the west Auckland suburb of Ranui, requiring two trucks to extinguish them.
The chaos comes just two days after FENZ urged Kiwis not to get "loose" with fireworks due to unusually dry conditions around the country.
"For a lot of people complacency kicks in and people get a bit loose with how they use fireworks - and it is those people who are causing lots of injuries and a number of fires," FENZ spokesperson Todd O'Donoghue told The AM Show on Monday.
Meanwhile, Auckland's Tūpuna Maunga Authority says Tuesday night's fires were the "last straw", and will close all public access to maunga in Auckland at Guy Fawkes while fireworks are still available for public sale.
"These fires are serious - they cause significant harm to these iconic taonga and pose a real risk to people and property," authority chair Paul Majurey said.