A freak storm described as a tornado by onlookers hit New Zealand’s largest city Auckland, with reports saying that at least three people were killed in ferocious winds.

The storm struck today in suburban Hobsonville, toppling trees, ripping roofs from houses and sending debris flying.

The New Zealand Newswire reported two deaths occurred when a concrete slab landed on a truck, while the New Zealand Herald said police sources had confirmed three deaths.

A further seven people were being treated for injuries, Fairfax Media said.

Construction worker Sam Nuttall said the storm, which officials said packed wind gusts of up to 110 kilometers an hour, struck without warning.

“You couldn’t see it coming,” he told reporters.

“There was debris flying everywhere, steel flying around. I’ve never been in weather like that before.”

Police could not immediately confirm the reported deaths but said there was widespread damage.

“It seems there’s been a couple of twister-like tornadoes that have come through and done the damage,” a police spokeswoman said.

“We’re still assessing the situation at the moment.”

A spokesman for the Metservice meteorological agency said it was too early to say whether the storm was a tornado.

“We’ve had no visual confirmation,” he said. “The situation we have is a line of intense thunderstorms across Auckland and much of Northland.”