A house has been gutted in the Port Hills fire, as emergency services battle the blaze raging through Christchurch for a second day.
With no end in sight, the inferno has spread and now covers an area of 650 hectares with a 14km perimeter since it broke out Wednesday afternoon.
The main fire was around Summit Road and a fire break was established at Worsley Spur to Dyers Pass Road.
About 80 Fire and Emergency firefighters and 27 fire appliances were at the scene supported by 14 helicopters and two aircraft dropping retardant.
Two bulldozers and a digger were being used in the battle to bring the blaze under control.
The cause of the fire remains unknown. The blaze response is being coordinated by multiple agencies including FENZ, Police, St John, and councils.
Fire and Emergency region manager Brad Mosby said even if the fire was contained today, it would still take days to mop up. Crews would not leave until they were sure it was fully extinguished.
Firefighters working through the night will concentrate on protecting buildings and strengthening containment lines.
Twenty-three crews will be working overnight.
Residents living on Christchurch's Port Hills are being warned they may notice more smoke overnight - including in areas that have not been affected today.
Fire and Emergency Incident Controller Stephen Butler says a shift in the wind is forecast overnight which will cause more smoke, possibly in areas that were not affected on Thursday.
He says evacuated residents who need to return to their homes to feed animals or carry out other essential tasks, can discuss their situation with Fire and Emergency staff at the community hub on Worsleys Road from eight o'clock this morning.
Damage
Fire and Emergency commander Dave Stackhouse said a container house appeared to have been destroyed by the flames.
The loss was not immediately apparent due to the nature of the home, but emergency services would be contacting the resident to offer support, he said.
"It is clear this fire is going to be a long-duration incident."
The Christchurch Adventure Park confirmed that the fires entered the boundary of the park last night and that there had been some damage sustained to trees at the top of the hill and to some of its ziplines.
The lift infrastructure was currently not believed to be affected and the chairs were removed from the line yesterday. The village is also currently unscathed.
The park will remain closed until further notice.
A state of emergency was declared Wednesday evening for Christchurch City, including Banks Peninsula, and Selwyn District.
Some evacuees return
Residents in Hoon Hay Valley and Early Valley were allowed back home.
But, 80 homes still remain evacuated and will be empty for a second night. Residents on Worsleys Road, Worsley Spur, Kennedys Bush have been evacuated.
Canterbury Civil Defence group controller Richard Ball acknowledged it would be difficult for those facing a second night out of their home.
Worsley Road residents who urgently needed access to their homes to get items should go to the community hub on Worsley Road before nightfall.
Te Rūnanga o Ngāi Tahu said it was aware of a small number of Ngāi Tahu whānau and kaimahi were among the people evacuated.
Port Hills resident Vicki Pflaum, whose house was destroyed in the 2017 fires, had to evacuate this time. She was allowed back in for 15 minutes to grab items.
It was retraumatising, Pflaum said, but it was a relief to see no burnt land around the property.
Another Port Hills resident Dominique Leeming said she and her partner "loaded up" two cars with their belongings before leaving the home. She could see the flames nearing her neighbour's house.
Residents in the Port Hills are asked to stay vigilant and continue to have a go bag ready in case further of evacuations.
Community steps up
Councillor for Halswell Ward Andrei Moore said there had been overwhelming help from a community remembering the devastation of fires in 2017.
"We're talking multiple offers every hour. The local vets here in Halswell have offered a safe place for animals, Dominos Halswell have delivered us pizzas, Halswell Bakery have delivered plenty of beautiful pies, the local Craythorne's Hotel have even made sure that some evacuees have a safe place to stay."
Moore said many residents staying at the community centre were worried about when they would be able to return to their homes.
Smoke spread being monitored
Crown forestry research institute, Scion fire scientist Hugh Wallace, said it was important thing was to have a plan, but the weather would drive things.
Scion was using weather information to monitor the smoke spread and would share that with authorities and the public.
"We found it's a really useful tool, especially for members of the public who have health issues that are affected by particulate and smoke. Quite often they'll use it to check where the smoke is coming from, whether or not it's a concentration that's particularly dangerous for them."
Scion may also be called in to run predictive modelling when the FENZ teams needed a break, Wallace said.