Hurricane Irma, one of the most powerful Atlantic storms in a century, is heading directly towards Florida after it lashed the Caribbean with devastating winds and torrential rain, killing at least 14 people and leaving a swathe of destruction. The "extremely dangerous" hurricane was downgraded from a category 5 to a category 4 early on Friday, but the US National Hurricane Centre warns it still packs winds as strong as 155 miles per hour (250kmh).

Irma has ravaged a series of small islands in the northeast Caribbean, including Barbuda, Saint Martin and the British and US Virgin Islands, ripping down trees and flattening homes and hospitals. Barbuda, where one person died, was reduced "to rubble", Prime Minister Gaston Browne said. In the British overseas territory of Anguilla, another person was killed and the hospital, and airport and power and phone services were damaged, emergency service officials said.

Hurricane Irma destroys tiny island of Barbuda Reuters

Prime Minister Edouard Philippe said four bodies were recovered on the French-Dutch island of Saint Martin, which was hit hard.

Another four people died in the US Virgin islands, a government spokesman said, and a major hospital was badly damaged by the wind.

The death tolls on both Saint Martin and the US Virgin Islands could rise because rescue teams have yet to get a complete look at the damage.

Authorities described the damage as catastrophic and said crews were struggling to reopen roads and restore power.

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The aftermath of Hurricane Irma on Sint Maarten, the Dutch half of the Caribbean island of Saint MartinNetherlands Ministry of Defence/Gerben van Es/Reuters
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WATCH: Live video shows Hurricane Irma battering Maho Beach in Sint Maarten PTZtv.com via Storyful

Three people were killed in Puerto Rico and around two-thirds of the population lost electricity, Governor Ricardo Rossello said after the storm rolled by the US territory's northern coast. Power lines and towers were toppled, leaves were stripped off plants and trees, a water and sewage treatment plants was heavily damaged and the harbour was in ruins, along with hundreds of homes and dozens of businesses.

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The streets of Fajardo are littered with debris after Hurricane Irma howled past Puerto Rico. (Photos: Alvin Baez/Reuters, Ricardo Arduengo/AFP)
1 Million Lose power in Puerto Rico after Hurricane Irma hits Wochit

The storm passed just to the north of the island of Hispaniola, shared by Dominican Republic and Haiti, causing some damage to roofs, flooding and power outages as it approached the impoverished Haitian side, which is particularly vulnerable to hurricanes and rain, although it did not make landfall. A man was reported missing after trying to cross a river in Cerca La Source in Haiti's Central Plateau region. Officials warned the death toll could rise in Haiti, where deforested hillsides are prone to devastating mudslides that have wiped out entire neighbourhoods of precariously built homes in flood zones.

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Residents look out of their house in the La Cienaga neighbourhood as Hurricane Irma approaches the Dominican RepublicErika Santelices/AFP
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People walk through debris and flooding in Puerto Plata, Dominican Republic. (Photos: Ivan Alvarado/Reuters, Ivan Alvarado/Reuters)
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People walk past a fallen stadium lighting tower in Puerto Plata, Dominican RepublicIvan Alvarado/Reuters
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People brace themselves for the arrival of Hurricane Irma in Cap-Haitien, Haiti. (Photos: Hector Retamal/AFP, Andres Martinez Casares/Reuters)

Cuba started evacuating some of the 51,000 tourists visiting the island, particularly 36,000 people at resorts on the northern coast. In Caibarien, a coastal town in the hurricane's predicted path, residents were heading farther inland.

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Left: Police escort a convoy of buses carrying tourists evacuated from Caibarien in Cuba. Right: Cubans carry their belongings as they evacuate their homes in Caibarien. (Photos: Adalberto Roque/AFP)
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A family removes a TV set from their home prior to the arrival of Hurricane Irma in Caibarien, CubaAlexandre Meneghini/Reuters

Irma is the strongest hurricane ever recorded in the Atlantic Ocean and one of the five most forceful storms to hit the Atlantic basin in 82 years, according to the NHC. Florida is preparing for Irma's wrath, with forecasters warning the storm could slam headlong into the Miami metropolitan area of six million people on Sunday, pummel the entire length of the state's Atlantic coast and then move into Georgia and South Carolina.

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Hurricane Irma moves across the Caribbean and heads towards the Florida coast in this satellite photo taken at 03:30 UTC on September 7, 2017.NOAA GOES Project via Getty Images

More than a half-million people in Miami-Dade County were ordered to leave as Irma closed in. In Miami, hundreds lined up for bottled water and there were huge queues of waiting to fill up with petrol. In Palm Beach, the waterfront Mar-a-Lago estate owned by US President Donald Trump was ordered to be evacuated. Trump also owns property on the French side of Saint Martin, the Caribbean island devastated by the storm.

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People pack up their car to evacuate as Miami Beach prepares for the approach of Hurricane IrmaMark Wilson/Getty Images
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People queue for wood for boarding up windows outside a Home Depot store in Miami. (Photos: Saul Loeb/AFP)
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Workers board up doors and windows at Mango's, a salsa club in Miami BeachSaul Loeb/AFP
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Inmate trustees from the Brevard County Jail work to fill and load sandbags for residents in Meritt Island, Florida. (Photos: Brian Blanco/Getty Images)
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A nearly-deserted beach is seen after residents and visitors evacuated from Miami BeachSaul Loeb/AFP
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Left: People walk past empty shelves where bread is normally sold in a Walmart store in North Miami Beach. Right: Shelves that are normally filled with bottles of water are empty at the Winn Dixie in Tavernier, Florida. (Photos: Carlo Allegri/Reuters, Marc Serota/Getty Images)
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Jorge Porro watches as a forklift is used to take his boat out of the water in preparation for Hurricane Irma in Key Biscayne, FloridaJoe Raedle/Getty Images
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Left: People enter a boarded McDonald's in Fort Lauderdale, Florida. Right: A worker puts tape on windows at a Dunkin Donuts store in Miami. (Photos: Michele Eve Sandberg/AFP, Saul Loeb/AFP)
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People crowd Fort Lauderdale International Airport as evacuation is underway for the arrival of Hurricane IrmaMichele Eve Sandberg/AFP
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Left: A sign warns about trespassing as residents and tourists evacuate Miami Beach. Right: A sign on a boarded-up business is pictured in North Miami Beach. (Photos: Saul Loeb/AFP, Carlo Allegri/Reuters)
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Fritz Drinks, whose family is from Haiti, helps load sand bags at Little Haiti Hardware and Lumber. Many people in this area won't be leavingCarolyn Cole/Los Angeles Times via Getty Images

Brian McNoldy, a hurricane researcher at the University of Miami, said Irma could easily prove to be the costliest storm in US history. Irma comes after Hurricane Harvey claimed about 60 lives and caused property damage estimated at as much as $180 billion in Texas and Louisiana.