SUVA, Fiji (AFP) - Relief supplies began arriving in cyclone-devastated Vanuatu Sunday as the Pacific nation declared a state of emergency amid reports entire villages were "blown away" when a monster storm swept through.
The official death toll in the capital Port Vila stood at six, although aid workers said this was likely just a fraction of the fatalities nationwide.
Communications were still down across most of the archipelago's 80 islands, although the airport in Port Vila reopened with limited facilities to allow much-needed aid in.
Two Australian air force planes landed with food, shelter and medicine while a New Zealand military aircraft also arrived loaded with eight tonnes of tarpaulins, water containers, chainsaw packs and generators.
Commercial flights were scheduled to resume on Monday.
The government said it was still trying to assess the scale of the disaster unleashed when Super Cyclone Pam, a maximum category five system, vented its fury on Friday night, with winds reaching 320 kilometres an hour.
The UN had unconfirmed reports that the cyclone had killed 44 people in one province alone and Oxfam said the destruction in Port Vila was massive, with 90 percent of homes damaged.
"This is likely to be one of the worst disasters ever seen in the Pacific, the scale of humanitarian need will be enormous... entire communities have been blown away," said Oxfam's Vanuatu director Colin Collet van Rooyen.
Vanuatu Red Cross president Hannington Alatoa said: "Effectively the whole country.. is flattened."
While the focus was on Vanuatu, Tuvalu - some 1,550 kilometres to the northeast - saw thousands forced from their homes.
The dire situation prompted Pope Francis to send a message of support.
"I express my solidarity to the people of Vanuatu... I pray for the dead, the injured and the homeless," said the pontiff.
Pictures from Port Vila showed streets littered with debris, cars crushed by trees, buildings blown to pieces and yachts washed inland.
Vanuatu police commissioner Colonel Job Esau said some areas of the capital - such as shopping districts and the waterfront - had been put off limits to try to stop looting as darkness approached - including possible thefts from yachts that had been washed away.
Ivan Oswald, an Australian cafe owner who has lived in Vanuatu for 13 years, said he had seen "opportunistic looting" of houses and boats.
"It's a sad thing... I've seen some people running around and started looting. Resorts are being pilfered. It's just getting a bit lawless at the moment," he told AFP by phone.
Oswald's Port Vila harbour cafe was "smashed up" by the cyclone.
"People are behaving differently. Some are fixing things, some are unable to, they are just a little bit shell-shocked," he said.
Vanuatu's President Baldwin Lonsdale described the storm as "a monster that has devastated our country", his voice breaking as he described Port Vila's devastation.
"Most of the buildings have been destroyed, many houses have been destroyed, school, health facilities have been destroyed," he told the BBC from Japan, where he was attending a disaster management conference when the cyclone hit.
Aid workers described scenes of desperation following what Unicef spokeswoman Alice Clements said was "15-30 minutes of absolute terror" as the cyclone barrelled into the island.
"People have no water, they have no power, this is a really desperate situation right now. People need help," she told AFP.
Clements said most of the dwellings on Port Vila's outskirts, largely tin shacks, stood no chance. World Vision spokeswoman Chloe Morrison said the situation also appeared grim for outlying islands in the nation of around 270,000.
"We're seeing whole villages and houses blown away," she said.
The Fiji-based head of delegation for the Red Cross in the Pacific told AFP she spoke with a man who flew a light aircraft Sunday to the southern island of Tanna, home to 34,000 people.
"He said all the corrugated iron structures he saw in the western part of Tanna were destroyed and all concrete buildings were without roofs," Aurelia Balpe said.
"All foliage was destroyed, there was no water and there were unconfirmed reports of two dead.
"Shelter and food are the major issues," she added. "We are still struggling to understand the number of casualties."
Save the Children's head of humanitarian response Nichola Krey raised fears of food shortages in the subsistence economy and said conditions in evacuation centres were challenging.
"Many of the evacuation centres have lots of women and young children sleeping cheek-by-jowl, so health and protection will be key in the coming weeks," she said.
Despite the problems, relief began to trickle in to Vanuatu, a day after Lonsdale made an emotional call for international aid.
New Zealand also flew supplies to Tuvalu, where Prime Minister Enele Sopoaga said 45 percent of the 11,000 population had been displaced.
Other Pacific nations were also struggling to cope. The Solomon Islands and Kiribati were both battered by the storm, although not to the extent of their neighbour.