Widespread damage has been reported only hours after Hurricane Beryl first made landfall in the southeastern Caribbean.
Roofs were ripped off buildings, trees were uprooted and electricity lines brought crashing to the ground on several islands when the ferocious storm swept in earlier on Monday.
Winds of up to 150mph were reported in some areas, with schools, businesses, airports, and government offices forced to close. There were also warnings that power outages and water cuts were likely.
It comes following forecasts that the hurricane was likely to be “extremely dangerous“.
Officials say it is the earliest ever time of the year that a storm of Category 4 strength has formed in the Atlantic, fuelled by unusually warm waters.
The previous record was held by Hurricane Dennis, which reached the threshold on July 8 in 2005 and went on to kill scores of people in the region.
Grenada’s national disaster co-ordinator Terence Walters said he had already received “reports of devastation” from Carriacou and the surrounding islands.
Grenada’s prime minister Dickon Mitchell said a hospital’s roof had been damaged, forcing the evacuation of patients to a lower floor.
He told reporters: “There is the likelihood of even greater damage. We have no choice but to continue to pray.”
NBC Radio in St Vincent and the Grenadines said it received reports of roofs being torn off churches and schools, with communication networks also collapsing.
The country’s prime minister Ralph Gonsalves said he expected the natural disaster to continue for days.
“We have to wait this monster out,” he said in an address to the nation.
Officials in Barbados said they had received more than a dozen reports of roof damage, fallen trees and damaged electricity lines.
Wilfred Abrahams, minister of home affairs and information, said drones would assess the damage once the hurricane had passed.
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Those living on nearby Caribbean islands are also bracing themselves for the hurricane’s coming onslaught.
Storm warnings are in place for St Lucia and Martinique, as well as parts of Haiti and the Dominican Republic. A hurricane watch has also been issued for Jamaica.
The US National Hurricane Center reiterated warnings that “this is an extremely dangerous and life-threatening situation”.
A spokesperson added: “Beryl is forecast to remain a significant hurricane during its entire trek across the Caribbean region”.
Waves crash into a sea wall in Trinidad and Tobago on Monday as the hurricane approaches. Pic: Reuters
The last strong hurricane to hit the southeast Caribbean was Hurricane Ivan 20 years ago, which killed dozens of people in Grenada.
Scientists have said climate change has made more intense, and earlier, storms more likely.
Christopher Rozoff, from the United States’ National Center for Atmospheric Research, said: “Climate change is loading the dice for more intense hurricanes to form”.
The hurricane is expected to weaken slightly as it later travels over the Caribbean Sea just south of Jamaica, before heading towards Mexico as a Category 1 storm.