A massive blaze at Tongariro National Park has grown to an estimated 1300ha and remains out of control, firefighters say.
Fire and Emergency NZ told 1News eight ground crews, nine helicopters, and five fixed-wing aircraft were battling the fire, with the expectation crews would be at the fireground for a week.
Dozens of hikers have been evacuated from two huts, with State Highway 47 Waimarino to Tongariro, the Tongariro Crossing and Northern Circuit remaining closed.
"Further evacuations are likely," a FENZ spokesperson said.
"We're asking those who don’t need to be here to please stay away, and for those nearby to please close their windows."
Earlier, new crews of firefighters from Taranaki and Manawatu-Wanganui were briefed before beginning work on the second day of operations at the scene.
The fire was reported on SH47 just north of the junction with SH48 at 3.15pm yesterday.
Assistant Commander Nick West said that because of the terrain and extent of the fire, air attack is more effective at this stage than bringing in additional ground crews across most of the fireground.
"There are no reports of structures being damaged or destroyed and no residents were evacuated overnight," a FENZ spokesperson said.
"An aerial reconnaissance this morning will confirm the extent of the fire. The cause of the fire has not been established.
"A specialist wildfire investigator will be working today."
The Department of Conservation said 43 hikers and the hut warden were evacuated by helicopter from Mangatepopo Hut last night, with a further nine people being evacuated from the Waihohonu Hut this morning.
"People are asked to stay away from the area, including Whakapapa and the section of the Northern Circuit accessible from Desert Road. The Tongariro Crossing and Northern Circuit, and other tracks and huts in the area including day walks from Whakapapa Village, will be closed for at least Sunday and Monday," said central North Island operations director Damian Coutts.
"The fire has been burning in the Mangetepopo Valley area and it’s too early to say if it has caused any damage to the tracks in the area. At this stage there are no reports of damaged huts or structures.
"We expect there will be significant biodiversity impacts given the size of the fire. Staff will assess this when it is safe to do so. The Mangatepopo Valley area is an important alpine ecosystem."
Residents in the area have been urged to stay alert to the fire, and keep doors and windows shut to minimise exposure to the smoke.
"Anyone who feels unsafe, or is vulnerable to smoke is encouraged to self-evacuate and stay with family or friends. Those to the north of the fire should go towards Turangi and those to the south of the fire should go towards National Park."
A no-fly zone was in place covering the airspace over the fireground and the surrounding area.
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