Deadly Hurricane Ike has roared across Cuba, blowing homes to rubble and sending waves crashing over apartment buildings.
Some 900,000 Cubans evacuated, and forecasters said it could hit Louisiana or Texas this weekend.
Ike, which raked the Bahamas and worsened floods in Haiti that have killed 321 people, made landfall on Cuba as a fearsome category three hurricane, then weakened to a still-potent category two on Monday as it ran along the length of the island.
There were no immediate reports of deaths in Cuba, despite storm-whipped waves that crashed into five-story apartment buildings, hurling heavy spray over their rooftops, and winds that uprooted trees and toppled utility poles.
By early afternoon, Ike had moved just offshore, giving it fuel to maintain its strength over Cuba, said Felix Garcia, a meteorologist at the National Hurricane Centre.
"It's over warm waters," Garcia said.
"It can definitely maintain its strength right now, and when it's out of Cuba it has the potential to become a lot stronger."
Ike is forecast to hit Havana, where decaying, historic buildings are especially vulnerable, before moving into the Gulf of Mexico and slamming into the United States.
As the hurricane's eye passed just south of Camaguey, falling power poles crushed cars parked along narrow streets and the roaring wind blew apart some older buildings of stone and brick, leaving behind only piles of rubble.
Cuban state television reported widespread rainfall of more than 100 millimetres, with more than 210mm in some places.
Families huddled inside their homes, watching from behind the iron gates of doorways as diagonal sheets of stinging rain fed rising flood waters.
The Cuban news agency AIN reported damage to several historic structures, including the 200-year-old fortress of La Punta, built near Cuba's eastern tip to protect against pirates.
Five-metre waves damaged the 18th century seawall of Baracoa in eastern Cuba, it said.
In Camaguey, a UNESCO world heritage site, colonial columns were toppled from buildings and the ornate sculptures on the roofs of centuries-old buildings were smashed.
Sporadic reports from six of the eight eastern provinces affected indicated that at least 900,000 people had evacuated, and former President Fidel Castro released a statement calling on Cubans to heed security measures to ensure no one dies.
Cuba historically has successfully carried off massive evacuations before hurricanes, sparing countless lives.
State television said officials had taken measures to protect thousands of European and Canadian tourists at vulnerable seaside resort hotels.
More than 9,000 foreigners were pulled from the Varadero resort, east of Havana.
A few street signs were topped at the US naval base at Guantanamo Bay in southeast Cuba and power went out temporarily in some residential areas, Navy Petty Officer 1st Class Robert Lamb said.
But the military said cells containing the detainees - about 255 men suspected of links to the Taliban and al-Qaeda - were hurricane-proof, and no injuries were reported.
By Monday afternoon, Ike had maximum sustained winds of 160 kilometres per hour about 130 kilometres west of Camaguey.
Ike was expected to hit Havana, 405km away, early Tuesday.
Officials closed schools and seaside avenues in the capital of two million people and prepared for evacuations.
Florida cancelled an evacuation order from its Keys on Monday as Ike moved further south, but urged tourists to stay away until Wednesday.
After passing into the Gulf of Mexico, forecasters said Ike could hit land over the weekend near the Texas-Louisiana border, possibly not far from Houston.
Ike first slammed into the Turks and Caicos and the southernmost Bahamas islands as a mighty category four hurricane that peeled off roofs and knocked down buildings.
In flooded Haiti, Ike made an already grim situation abysmal.
