Vanuatu has been devastated by Cyclone Pam. Up to 40 may be dead.

At least four people have died in Vanuatu’s capital of Port Vila, a witness says, in one of the strongest tropical cyclones to have hit the South Pacific.

It comes amid unconfirmed reports that more than 40 people may have perished elsewhere in Vanuatu as a result of Cyclone Pam.

One person has also died in Papua New Guinea’s West New Britain province after a tree fell onto a house during strong winds driven by the storm.

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Vanuatu coordinator of climate change not-for-profit organisation 350, Isso Nihmei, said he and others tried to rescue three people in Port Vila who later died in hospital.

“We heard some of the people who were living close. They were shouting and calling us. So once we went down there, we saw this guy who was already dead,” he said.

“There [were] other people on the other side, so we went down to rescue them but they were really weak.

“We got them to hospital but they died in half an hour.”

Mr Nihmei said they had injuries to their faces and bodies and were living close to the sea. He said they had chosen to stay because of their boats.

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Power and communications are down across much of the country which has made it difficult for authorities to confirm damage and a death toll.

Humanitarian organisations have warned of “complete annihilation” in Port Vila, where the cyclone reportedly tore through at 340 kilometres per hour.

But some fear the devastation could be even worse in the outer islands.

The United Nations Office for the Coordination of Humanitarian Affairs said there were no official reports of deaths or injuries, but there was an unconfirmed report that 44 people died in the central Penama province.

Pam was about 280 kilometres south of Tanna, in Vanuatu’s southernmost province, at 4:00pm (AEDT), moving southwards at 41 kilometres per hour, according to Vanuatu’s Meteorological Services.

Residents of Port Vila spent the night bunkering down as the terrifying storm raged, waking to find trees had been uprooted, homes destroyed and areas flooded.

Thousands need emergency accommodation

Save the Children Vanuatu country director Tom Skirrow said an estimated 10,000 people would need emergency accommodation in the capital.

He said it could be up to eight weeks before people were able to get back to re-build their houses.

“As people stayed in their houses last night they certainly won’t want to stay in them now given the state of them,” he said.

“So there’ll probably be about 10,000 people in the evacuation centres just in Port Vila alone.”

He said it was still difficult to determine the impact of the storm because phone lines were down across the country.

“All we know for sure is a cyclone like this will have wrought significant devastation across the country,” he said.

He said the clean-up effort had started in Port Vila but was minimal.

“There are only so many staff available from the public works department. Some people have started to go out and clear some roads so that access is possible but only the main thoroughfare roads.”

Alice Clements, a spokeswoman for the UN Children’s Fund (UNICEF), in Port Vila said the damage was likely to be great.

“It felt like the world was going to end. It’s like a bomb has gone off in the centre of the town. There is no power. There is no water,” she said.

“We are hearing unconfirmed reports of casualties and lots of wounded. People are asking for help.

“Even in Port Vila there are still gale-force winds.”

Australia’s Foreign Minister Julie Bishop said Australia’s High Commissioner in Vanuatu, Jeremy Bruer, had spoken to the country’s prime minister to offer assistance.

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“We are deeply concerned by reports that lives have been lost in northern Vanuatu,” Ms Bishop told reporters.

“They are still unconfirmed but we are deeply concerned by those reports.”

She said there had been no reports of Australian deaths but said there were more than 800 Australians registered in Vanuatu. She said that number, however, could exceed 3,000.

Queensland Premier Annastacia Palaszczuk has also offered assistance. She said specialist crews could be deployed to the area to help restore power if needed.

Vanuatu houses ‘hit by 340kph wind gusts’

Save the Children’s Head of Humanitarian Affairs, Nichola Krey, said the storm was as severe as feared.

“It hit Port Vila at an incredible 340 kilometres an hour,” she said.

“Some reports are saying it was at that speed, so you can imagine the flimsy housing in Vanuatu made of corrugated iron and very weak wood.

“You can imagine what 340 kilometres an hour wind does to that.”

CARE Vanuatu program manager, Charlie Damon, said she had also received unofficial reports of fatalities.

Ms Damon, speaking from Port Vila, said most roads were blocked by fallen trees and it was still quite dangerous to go outside.

She said even evacuation centres were damaged.

“Some have been flooded and some evacuation centres have also lost parts of their roofs too, but those on the outer islands they certainly will be feeling the brunt of this as they just don’t have the facilities as we do in Port Vila,” she said.

Red alerts remain in place for some provinces

The Vanuatu Meteorological Services warned very destructive hurricane-force winds of 250 kilometres per hour continued to affect the country’s southern provinces today.

A red alert remained in place for Tafea province.

It said the central pressure of the system was estimated at 900 hectopascals, which is among the strongest tropical cyclones on record.

Australian Bureau of Meteorology senior forecaster Simon Allen said severe tropical cyclones could be difficult to forecast.

“The track, I think, was always for some time likely to be close to Port Vila but it did move a bit closer than we expected in the end, so the eye of the cyclone ended up very close to the capital,” he said.

“In a couple of days it’s likely to move to the east of New Zealand, but despite that it will still have significant impact on the northern and eastern parts of the North Island of New Zealand in particular.

“So [we are] likely to see some heavy rain, damaging winds and possibly storm surges in those areas as well as we go into next week.

“But hopefully less force there.”

This story originally appeared on the ABC website and is republished here with full permission.