Cuba has been plunged into darkness after Hurricane Rafael slammed into the island as a Category 3 storm with sustained winds of 115mph (185kph).
The country's electricity operator UNE said high winds had caused the electricity grid to collapse.
State-run TV reported the entire population of 10 million people was without power - part of a series of blackouts which have plagued the Caribbean island in recent weeks.
Rafael lashed Cuba's capital Havana late on Wednesday afternoon, with wind and rain bringing down trees and power lines in the city.
The US-based National Hurricane Centre (NHC) warned of a "life-threatening storm surge, damaging hurricane-force winds and flash flooding" across much of western Cuba.
Schools and public transport in the city were suspended and flights were grounded, while police with loudspeakers began circling neighbourhoods encouraging people to shelter.
Last month Cuba suffered a total collapse of its national electric grid, leaving an estimated 10 million people without power for several days.
That coincided with Hurricane Oscar making landfall around the same time.
Cuba's oil-fired power plants have struggled to secure vital oil imports from Venezuela, Russia and Mexico.
Rafael brushed past the Cayman Islands as a Category 1 hurricane before increasing to a much more powerful Category 3 storm off the southwest of Cuba.
The most recent update from the NHC said it had weakened to category 2, with maximum sustained winds of around 105mph (170km) off the northwestern coast of Cuba.
Forecasters have predicted 4 to 8in (10 to 20cm) of rain across parts of western Cuba and up to 12in (30cm) on higher ground, bringing the risk of flash flooding and mudslides.
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Rain and strong winds have also affected the Florida Keys.
Forecasters predict Rafael will spin off towards the western Gulf of Mexico over the next few days, although the track remains uncertain.
(c) Sky News 2024: Hurricane Rafael crashes into Cuba triggering island-wide power blackout
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