Firefighters were focused on protecting people's homes overnight as wildfires in the Port Hills continued to spread.
Civil defence hastily corrected its report late on Wednesday night that 40 houses had been engulfed in the Port Hills fires, saying instead that three had burnt down.
Hundreds more people were evacuated late yersterday evening as the battle against the huge fires continued.
Wildfires which have been burning on the Port Hills since Monday have been advancing towards the city today after a big wind shift.
Overnight, the fires merged into one large blaze in excess of 1850 hectares.
Civil defence said the fire was still growing and could spread even closer to residential areas overnight, fanned by fresh easterly winds.
The three houses civil defence confirmed had been destroyed were in addition to five homes that were razed on Tuesday and Wednesday.
Ground crews are still monitoring the fires but fourteen helicopters that were helping to douse the flames were stood down overnight.
Selwyn's principal rural fire officer Douglas Marshall told RNZ that firefighters would be unable to fight the flames overnight, and instead their priority would be protecting people's homes.
Earlier, the fire service said the fire was not out of control, but Mr Marshall said things had got much worse in the past few hours.
The Christchurch City Council said up to 400 people were evacuated from Westmorland and Cracroft on Wednesday afternoon as the fire advanced today, with hundreds more choosing to leave voluntarily.
That number swelled as police and the defence force led further evacuations in Westmorland and Cashmere Hills from about 9.30pm, after the fire jumped Dyers Pass Road.
All residents in the area between Sign of the Takahe and Victoria Park were told leave their homes immediately.
Civil defence said the south side of Cashmere Road to Kennedy's Bush Road and to Hoon Hay Valley Road was also being evacuated, in addition to earlier evacuations in the area.
People who had left their homes were now being directed to the Halswell Library, not the Pioneer Recreation Centre where they were initially sent.
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The Selwyn Events Centre in Lincoln was also being used as an evacuation centre, and Ngāi Tahu made Nga Hau e Wha Marae on Pages Road available for people needing assistance.
People living close to the fires have being told they must be prepared to evacuate at short notice.
The Selwyn District Council said the changes in the fire on Wednesday afternoon were largely due to the wind shifting to the north-east.
A spokesperson said fires were within an estimated 1655 hectare area, although not all of this area was alight as the fire had been extinguished in some locations.
The Marley Hill fire spread down Worsley Spur, causing extensive vegetation burning in the Christchurch Adventure Park, and was approaching the residential area of Westmorland.
Three houses were destroyed on Hoon Hay Valley Road on Wednesday afternoon, while the Early Valley Road fire also destroyed a house.
Christchurch police said there would be extra patrols out in the city tonight to assist those in the areas affected by the fires.
On Wednesday evening, the Selwyn District Council and Christchurch City Council declared a joint state of emergency, and the government said a local state of emergency will be declared sometime tonight.
Christchurch's Civil Defence emergency operations centre has been activated to help with evacuations.
Civil Defence Minister Gerry Brownlee said he was unhappy with how unclear things had been, and said he did not understand why a state of emergency was not declared earlier.
Residents 'chased out of the house'
A Westmorland resident, Anne, said her husband, Neil, was still at home with the car packed in case police told him to evacuate.
She could not get to her Penruddock Rise property as police were not letting residents back into the hillside suburb.
She said he had never seen anything like the fire before.
Resident Vikki Pflaum, who was told to get out of her home about 3pm, grabbed photos and essentials while her builder husband's staff grabbed vital business files.
"The whole street has been evacuated," she said. "I had six policemen chase us out of our house."
They lived near the Christchurch Adventure Park. She said flames were all through the top of the park area and around the new gondola.
She remained optimistic things would be okay, but said she could not believe the numbers of rubberneckers parked up on the roadside to watch the fire.
Tens of thousands of Christchurch properties also lost power on Wednesday afternoon.
About 89,000 Christchurch properties in the north and east of the city lost power at some point, according to power company Orion, which has warned it could not rule out the possibility of further power outages overnight.
Smoke gets in your eyes
The change of wind today also saw the thick smoke from the fires blow right across Christchurch.
Canterbury District Health Board issued health advice over the smoke. Medical officer of health Alistair Humphrey said the smoke had noticeably spread over the city and surrounding hill suburbs.
He said for the vast majority of people, the smoke would be unpleasant, but carried no risk to their health.
However, smoke may irritate the eyes, nose, throat and airways.
He said people who had difficulty breathing, or had a prolonged cough or tightness in their chest should contact their doctor.
Dr Humphrey said most people were very unlikely to have any long-term health effects but people with pre-existing respiratory illness or heart disease may experience an exacerbation of their condition.
He said people should avoid exposure where possible, by staying indoors and closing windows and doors.
Sightseers wanting to look at the fires have also caused issues for emergency services, and authorities have asked people to stay away from the affected areas.
Nerve-wracking night for locals
The largest fire in the hills at Allandale in Governor's Bay near Christchurch started on Monday near Summit and Dyers Pass roads, and flared up again overnight - making its way down the hill towards the bay.
It came to within 100m metres of half a dozen homes, before being beaten back by helicopters dropping water.
Governors Bay fire chief Andrew Norris, said about 45 volunteer fire fighters spent the night stationed at the threatened houses protecting them.
Mr Norris said they were lucky helicopters with monsoon buckets arrived and stopped the fire early this morning.
He said at least half a dozen homes that were in the direct line of the fire would have been lost.
It was a particularly nerve-racking time at first light when a wall of flames spreading across 500m of pine plantation began advancing on Governors Bay, coming within a few hundred metres of it.
Flames leapt up to 20m in the air and ash began falling on residents as they watched to see whether it would catch on to the network of trees standing between them and the fire and send it directly towards them.
Wayne Parkhill and his partner spent most of Tuesday night watching the flames get closer to their property and were ready to leave at a moment's notice.
"I've got a boat there that's uninsured so that's one thing I'll definitely be taking and the other stuff that will have to stay. I'm a builder, I've got all my work tools in the car and my partner Annie, she's got everything packed that she can pack."
As the flames got closer Mr Parkhill wondered when the helicopters, which had fought the blaze until sunset the previous night, would return.
His prayers were answered about an hour after sunrise when three carrying monsoon buckets swung over the ridge from Christchurch.
They quickly began ferrying water from the sea to the fire and helped bring it under control.
About 27 people spent the night in the local school while others stayed with friends and family.
Mid-morning the Governors Bay residents were allowed to return to their homes after a change in the wind sent the fire back over the hill where it had come from.
Residents of the neighbouring settlement of Allandale have not been allowed back into their homes.
Firefighters have been working non-stop for three days now to get on top of the two fires and prevent them from joining up.
A volunteer with the Governors Bay brigade, Rob Brown, said he had had about two hours sleep since Monday.
"It's just one of those things, you keep going, what drives you I suppose is the desire to help other people really in the same situation, it's all we can do."
He was hopeful the end of the gusty north west winds that whipped up the flames yesterday would prevent a repeat of last nights evacuation but was ready to move again just in case.
Last night, Debbie Prior had to leave her home and went to a friend's house, where she could still see "masses of smoke".
"In the middle of last night, it was just like a big wall of fire," she said. "It was extraordinary. It was like watching a volcano erupt."
Temporary ban on drones around fire
Police have placed a temporary ban on using drones around the Port Hills.
They said people had been using drones to photograph the fire and that posed a major safety risk to helicopters.
Police said there was nothing to suggest a drone was involved in the death of helicopter pilot Steve Askin.
The Civil Aviation Authority has enforced a restricted airspace zone over Port Hills which will stay in place until Friday, but could be extended.
The police said anyone caught using a drone in the restricted area could face charges.
Givealittle page set up to help family who lost home to fire
A givealittle page has been set up to support a Christchurch family that lost their home to one of two fires burning on the Port Hills since Monday evening.
The fire, which started on Early Valley Road, has destroyed one home and killed livestock.
So far more than $2000 has been donated on a givealittle page, to help the family who lost their home.
A statement on the page says the family of four has been left with nothing but the clothes on their backs.
If you witnessed the fire and would like to share pictures or video with us, please email them to: firstname.lastname@example.org
- Cashmere Road is closed west of Kaiwara Street through to Kennedys Bush Road.
- Hoon Hay Valley Rd closed due to rubbernecking. Residents can still access their properties.
- Kennedys Bush Road is closed from the roundabout with Rock Hill Drive. This includes the southbound cycle track.
- Worsleys Track closed from Worsleys Road.
- Dyers Pass Road between Hackthorne Road to Governors Bay Road.
- Summit Road between Gebbies Pass and Rapaki Track.
- Old Tai Tapu Road between Osterholts Road and Early Valley Road.
- Early Valley Road is closed.
- Holmes Road is closed.
- Christchurch Adventure Park is closed.