Survivors of Hurricane Dorian in the Bahamas picked through the wreckage of homes ripped apart by fierce winds, struggled to fuel generators and queued for food on Wednesday, as Dorian bore down on coastal communities in the southeastern United States and regained intensity.
The most damaging storm ever to strike the island nation, Dorian killed at least 20 people, Prime Minister Hubert Minnis confirmed on Wednesday, reiterating that more fatalities were expected.
Aerial footage of affected areas revealed widespread devastation. The US Coast Guard and Britain's Royal Navy airlifted survivors and ferried in emergency supplies as the flood waters receded, and the United Nations said 70,000 people on Grand Bahama and Abaco islands were in "immediate need" of aid.
Mark Lowcock, the United Nations under-secretary general for humanitarian affairs, said in a conference call with reporters that he expected the death toll to rise significantly.
In the US the state of South Carolina was preparing for a record storm surge and major flooding with the potential for more than a metre of rain in places when Dorian makes landfall.
Late on Wednesday, the US National Hurricane Center upgraded the storm, which had been weakening after leaving the Bahamas, to a major Category 3. It had earlier been downgraded to Category 2.
Dozens of people in the Bahamas took to Facebook to search for missing loved ones.
"We are in the midst of one of the greatest national crises in our country's history," Minnis told a news conference.
"We can expect more deaths to be recorded. This is just preliminary information."
LaQuez Williams, a pastor at Jubilee Cathedral in Grand Bahama, who opened the church as a shelter for about 150 people, said he saw people on their rooftops seeking refuge.
"They were calling for help, but you could not go out to reach," Williams said. "It was very difficult because you felt helpless."
Aerial video of Great Abaco Island showed miles of flooded neighbourhoods littered with upturned boats and shipping containers scattered like toys. Many buildings had walls or roofs partly ripped off.
A Reuters photographer surveying the damage on Grand Bahama island said many hangars at Freeport airport and several aircraft appeared to be severely damaged.
'Something no one could prepare for'
A single Facebook post by media outlet Our News Bahamas seeking the names of missing people had 2,000 comments listing lost family members since it went live on Tuesday, although some of the comments were also about loved ones being found.
Janith Mullings, 66, from Freeport, Grand Bahama, said she had been through hurricanes all her life but had never seen anything like Dorian.
"We've never had hurricanes in none of our islands that have experienced the ocean rising like it did. The ocean was something no one could prepare for," she said.
A massive relief effort was underway with volunteers ferrying supplies to the islands in a flotilla of small boats.
As many as 13,000 homes in the Bahamas may have been destroyed or severely damaged, the International Federation of Red Cross and Red Crescent Societies said.
"It's heartbreaking ... ," said Caroline Turnquest, director general of Bahamas Red Cross. "We know from what we've been seeing and hearing, that this one will require the help of all the persons."
Food may be required for 14,500 people in the Abaco Islands and for 45,700 people in Grand Bahama, the UN World Food Programme said.
US Coast Guard and Customs and Border Protection workers have airlifted 61 people from the northern Bahamas to the capital Nassau over two days, the US Embassy said.
Dorian could strengthen
Meanwhile, Dorian is lashing the US coast. The hurricane was about 210km south of Charleston at 8pm (00:00GMT), the Miami-based National Hurricane Center (NHC) said.
It could strengthen further to a Category 4 in the next 24 hours "because it is hovering over warm waters, a key ingredient in hurricane intensity, NHC meteorologist Lance Wood said.
The NHC issued a storm surge warning that covered the whole length of the coasts of Georgia, South Carolina and North Carolina and extended to Hampton Roads in Virginia.
The NHC warned that Dorian would move near or over the coast of South or North Carolina on Thursday or Friday. More than 2.2 million people in Florida, Georgia, North Carolina and South Carolina have been ordered to leave their homes.
Florida avoided a direct hit from Dorian.
"We certainly got lucky in Florida, and now if we could get lucky in Georgia, in North Carolina, in South Carolina," President Donald Trump told reporters in the Oval Office.
Trump said the US was sending supplies to the Bahamas including materials that had been originally intended for Dorian victims in Florida.