Residents have been forced to swim to safety from flooded homes in New Zealand after Cyclone Gabrielle lashed the country's north.

The government announced a national state of emergency on Tuesday due to the storm's devastation - just the third time in history it has done so.

Prime Minister Chris Hipkins says the disaster is New Zealand's biggest weather event in a century.

Officials said at least 225,000 people were without power on Tuesday.

A firefighter remains missing after being caught in a landslide in Muriwai, west of Auckland. A second firefighter involved was critically injured, rescue agencies said.

The storm's damage has been most extensive in coastal communities on the far north and east coast of the North Island - with areas Hawke's Bay, Coromandel and Northland among the worst hit.

Nearly a third of New Zealand's 5.1 million population live in affected regions.

Marcelle Smith, whose family lives in a cliff-front property in Parua Bay on the east coast of the North Island, told the BBC she had fled inland with her two young children on Monday night to higher ground.

Her husband had remained behind to set up protections for their home. Some embankments set up had already been washed away and they were still battling wild weather on Tuesday.

“We are trying to do everything we can to protect what we have put our lives into. It's man versus nature at this point,” she told the BBC.

Local media have reported that some residents in Hawke's Bay had to swim through bedroom windows to escape as waters flooded their homes. People in the area have been warned they could be without power for weeks.

Aerial pictures of flooded regions showed people stranded on rooftops waiting for rescue.

The vast scale of the damage includes uprooted trees, bent street lights and poles, and row after row of flooded homes.

New Zealand's Defence Force released dramatic pictures of officials rescuing a stranded sailor, whose yacht was swept out to sea when its anchor cable snapped amid strong winds. It was located off Great Barrier Island after an overnight search mission, authorities said.

In Auckland, more than 100 people had also fled to evacuation centres overnight, officials said.

“The severity and the damage that we are seeing has not been experienced in a generation,” Mr Hipkins said on Tuesday.

“We are still building a picture of the effects of the cyclone as it continues to unfold. But what we do know is the impact is significant and it is widespread.”

He has pledged NZ$11.5m (£6m; US$7.3m) in aid to support those affected by the disaster.

Declaring the national state of emergency on Tuesday morning, the Minister for Emergency Management, Kieran McAnulty, described the storm as “unprecedented”.

The emergency order enables the government to streamline its response to the disaster. It has been applied to the Northland, Auckland, Tairawhiti, Tararua, Bay of Plenty, Waikato and Hawke's Bay regions.

New Zealand has only previously declared a national state of emergency on two occasions - during the start of the Covid-19 pandemic and following the 2011 Christchurch earthquake.

The government has attributed the scale of the disaster to climate change.

“The severity of it, of course, [is] made worse by the fact that our global temperatures have already increased by 1.1 degrees,” said climate change minister James Shaw.

“We need to stop making excuses for inaction. We cannot put our heads in the sand when the beach is flooding. We must act now.”

Cyclone Gabrielle has hit New Zealand just two weeks after unprecedented downpours and flooding in the same region, which killed four people.

The country's meteorological agency, MetService, on Tuesday said Auckland had received about half of its annual rainfall in just the first 45 days of 2023.

The MetService says conditions are expected to clear in coming days, and heavy rain warnings are being lifted for some parts of the country. But it has warned that wind could still cause further damage. (BBC)

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