John Bacon

USA TODAY

The death toll from Hurricane Matthew's furious blast across beleaguered Haiti rose to more than 280 people late Thursday night, while the Atlantic basin's most powerful storm in almost a decade continued its unrelenting march toward the U.S. East Coast.

An official from ​Haiti's Interior Ministry told the Associated Press that Hurricane Matthew claimed at least 283 people after the storm struck Tuesday with 145-mph winds, torrential rain and driving storm surge. Haitian Interior Minister Francois Anick Joseph called the death toll "very provisional," saying authorities had yet to complete a nationwide damage assessment.

Matthew, which has prompted evacuation orders for more than 2 million people from Florida to South Carolina. is the most powerful single hurricane on record to make landfall in Haiti, Cuba and the Bahamas. Other countries in the region also felt the storm's fury.

Matthew was smashing through the Bahamas on Thursday, and little information on damage was immediately available. At least four died in the Dominican Republic, Haiti's neighbor on the island of Hispaniola. Deaths also were reported in Colombia and St. Vincent and the Grenadines.

"We continue to collect information," said Haitian civil protection director Alta Jean-Baptiste. "We can tell you that there are communities ... where there is a lot of material damage and also loss of life."

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Peter Mulrean, the U.S. ambassador to Haiti, joined Jean-Baptiste and Haitian President Jocelerme Privert in surveying the damage from the air Thursday. The U.S. Agency for International Development pledged an additional $1 million in humanitarian assistance for Haitian communities, bringing the USAID total to $1.5 million.

The storm was a brutal blow to the impoverished nation of 10 million people still recovering from a 2010 earthquake that killed 200,000. More than 55,000 people were still living in tents and makeshift homes before Matthew roared through.

United Nations emergency response teams were on the ground in Haiti to coordinate rapid assessments and support disaster aid distribution. The nonprofit aid agency Mercy Corps said its teams in Haiti were confronting heavy damage to infrastructure and agriculture.

About 80% of the banana crop in Arcachaie, the biggest banana-growing region in Haiti, was destroyed, the group said. These crops supported more than 20,000 families, and farmers may have difficulty replanting the crops due to seawater flooding, the group said.

“We still don’t know how many people have lost their homes. The hardest-hit areas are still tough to access,” said Jessica Pearl, country director for Mercy Corps. “And we are very concerned that many families do not have access to clean drinking water, which greatly increases the risk of cholera."

More than 27,000 cases of cholera had been reported in Haiti this year before the hurricane struck, Pearl said.

Another nonprofit, World View, said that a preliminary assessment indicated that in the south, where Matthew's hit was direct, up to 80% of homes lost their roofs. In other vulnerable areas of the country almost half the homes were damaged, the group said.

“The biggest needs are water and temporary shelter," said John Hasse, World Vision's director in Haiti. "The entire NGO community is worried about cholera and other water borne disease outbreaks.”

In the Dominican Republic, Emergency Operations Center Director Juan Manuel Mendez said four people had died as a result of the hurricane, with more than 3,000 homes severely damaged or destroyed. He told Dominican Today the most severe damage occurred in western Vicente Noble, where an overflowing river set off a mudslide.

Simon Suarez, head of the Dominican Hotels and Tourism Association, told the newspaper the resort areas, ports and airports were not affected except for cancellations of several flights from Las Americas International Airport to Caribbean islands.

In New Providence, Bahamas, Ebony Thompson told The Nassau Guardian her family had to flee before the storm seemed very strong.

"At one point there wasn't anything, just a lot of breeze," she said. "Then the water went from nothing to 2 feet ... Then it started coming in the door."

In Cuba, the U.S. military evacuated 700 family members of service personnel from the Navy base at Guantanamo, and the Cuban government evacuated hundreds of thousands of residents before Matthew made landfall on the island's eastern tip late Tuesday. Homes were damaged and several cities were cut off when roads became blocked by storm debris, but no deaths were immediately reported.

USAID deployed a Disaster Assistance Response Team, described as "an elite team of disaster experts," to Haiti, Jamaica and the Bahamas. U.N. Humanitarian Response Depot in Panama was organizing charter flights to the region with supplies of water and sanitation, housing and non-food items.

“The world must stand with the victims at this time as people of goodwill everywhere recognize their suffering and stand ready to offer a helping hand," U.N. General Assembly President Peter Thomson said.