Three people are dead and seven injured after a tornado ripped through the Auckland suburb of Hobsonville, with police ordering people to shelter in their homes amid fears of further twisters.
The tornado, which hit about 12.15pm, ripped roofs from houses, toppled trees and sent debris flying on to cars.
Hobsonville Point residents have been ordered to take shelter in their homes and cars with the MetService warning of the potential for further tornadoes.
Police have set up an operational base at the worst-hit Whenuapai.
Twelve Urban Search and Rescue (Usar) members were in the area gathering intelligence and have been sent out into the field to check houses.
It's understood several downed power lines in the area are preventing search teams from getting to some buildings.
The Defence Force was cooperating with the response and is standing by but has not yet deployed personnel.
Andy Gummer from St John said: "So far seven people have been transported to North Shore hospital with minor and moderate injuries.
"People were treated on the scene then transported."
The injuries occurred in a 1 km-wide area.
Ambulance staff reported two deaths from the storm at a construction site in West Auckland. A third death was later confirmed.
There are reports of multiple injuries across the northwestern suburbs. A construction worker on a new high school site at Hobsonville told Radio New Zealand there were people missing and many people injured.
"Pretty bad," a man, quoted only as Sam, said.
"We did a head count, I think there are a couple of people missing."
An ambulance spokeswoman said five crews were attending different scenes.
"We are currently assessing seven patients all in and around Hobsonville."
Twenty fire trucks are dealing with 80 properties mainly in Hobsonville and surrounding west Auckland suburbs.
Roofs being blown off and flooding are the main problems being dealt with, fire communications shift manager Peter Stevenson said.
Earlier reports indicated people were trapped but they have since been rescued. However, there were potentially others trapped, Stevenson said.
North Shore Hospital's emergency department is assessing four patients with tornado injuries, though their status or the type of injury is not yet known.
Patients are being sent to North Shore because it has a larger emergency department than Waitakere.
Waitakere Hospital has suffered surface flooding in an outpatient area.
No one has been evacuated and the hospital is functioning as normal, communications spokeswoman Ashley Campbell said.
Power is out at the Hobsonville shopping area.
The New Zealand Transport Agency said State Highway 18, the upper harbour motorway, was closed between Brigham Creek Rd and Greenhithe Rd due to debris on the road.
Toni Hayward, administrator at the Open Wananga Office in Hobsonville, saw the tornado rip through.
"It came right through here and picked stuff up an threw it on the road."
"The sky went all dark and there was a big clap of thunder, all the trees were flattened."
There are now severe thunderstorm warnings for the Waikato area.
Hobsonville RSA cook Deborah Carlson said she was trapped in her car during the storm, too terrified to go outside.
"I was just sitting there because it was pouring with rain and I thought I'd wait it out. But then my car starting shaking and there were things flying everywhere. I thought it was going to flip, I was terrified."
Carlson said she didn't know what to do, so called her boyfriend.
"I was in there by myself for about 15 minutes. The bins were flying past and the gates were swinging open, it was horrible."
She said when she finally left the car, the scene was a mess: "There's debris everywhere."
Casey Davenport, who lives in Hobsonville, was at work when the weather started to turn.
"Then it just came down, and it looked like mini tornadoes - the rain was just like being swished around a lot."
"Then somebody gave me a call and said that somebody's house from work had been taken out and I was like 'oh God'. Not fun."
Fallen or uprooted trees and pieces of debris were blocking the road to her house, which she said now is "leaking like a sieve".
"We're missing tiles, broken windows...it's full of water now because it's leaking. But we're one of the better ones I think."
Brendan Muir, who is working at Hobsonville Point, said he was sitting in a ute when the tornado hit.
"It was just mayhem. I had to put my seat belt on, I thought it was going to flip."
Muir said that, around him, he could see trees "that looked like a plane had crashed into them", walls and fences knocked down and Portaloos scattered about.
He said for about 10 minutes there were so many sirens sounding it "seemed like 9/11".
Despite threats of another tornado on the way, Muir said he was back pouring concrete.
The storm has destroyed houses in the air force's married quarters in Clark Rd, Hobsonville.
A witness said the roof had been ripped form at least one house, and a tree had smashed through the kitchen of a house nearby.
Trees have been uprooted, a trampoline flipped and fences crushed by the force.
Frances Schuster said the tornado only lasted 12 seconds but was terrifying.
"It went blurry for a while, it just happened so fast. It was really loud and the windows were shaking."
Part of a roof fell on to her car.
PM, MAYOR RESPOND
A spokeswoman for Prime Minister John Key - the MP for Helensville, which includes Hobsonville - said he is being kept informed of the situation.
"Emergency services are currently responding. People are being advised to remain indoors and to avoid the area, if possible."
She added: "The Prime Minister will continue to assess the situation as information becomes available throughout the day."
Auckland Mayor Len Brown says he was very concerned at casualties on Hobsonville Point.
"Also reports of surface flooding and damage in other parts of Auckland. Please stay safe and if possible stay inside until the weather clears," he said on his Facebook page.
- Fairfax Media
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