KINGSTON (AFP) - Deadly Tropical Storm Gustav thrashed Jamaica Friday and was on track to crash into Cuba as a hurricane after leaving up to 78 people dead in the Dominican Republic, Haiti and Jamaica. Jamaica woke to a trail of devastation and reports that the storm killed as many as 11 people on the island as the storm moved toward the west, triggering flash floods and heavy rains. Gustav could become a "major hurricane" before reaching western Cuba on the weekend, the US National Hurricane Center warned. Streets in the normally bustling capital city of Kingston were soaked and quiet, except for howling winds as Gustav's powerful gusts sent metal roofs flying, and threatened to wreak havoc on Jamaica's banana industry, officials said. Maximum sustained winds slowed to 100 kilometers per hour early Friday. Around 1,500 people crammed into shelters to wait out the storm, which moved to the western side of the island early Friday. Later in the day, Gustav was forecast to head west-northwest towards the Caymans, an overseas British outpost and key banking center. Across the Cayman islands, resorts and residents shuttered their windows to guard against Gustav, which the National Hurricane Center said would likely regain hurricane strength later Friday or by Saturday. Cuba, with more than 11 million people, is extremely vulnerable to hurricanes, with most of its housing stock aged and in fragile condition. More than two million people live in the capital, Havana, where many colonial era buildings are prone to cave-in after heavy rains. Anxiety also was mounting on the US Gulf Coast on the third anniversary of Hurricane Katrina, as authorities in New Orleans mulled a possible mandatory evacuation to prevent a repeat of the devastation and deaths of 2005. Authorities in Louisiana and Mississippi have already declared states of emergency before Gustav's expected landfall late Monday, when it could strike as a powerful storm. After the devastation wrought by Katrina, the storm could show whether US authorities learned lessons from the tragedy " a major political disaster for the Republican US administration. Civil defense officials in the Haitian capital Port-au-Prince said Friday that 59 people died, seven went missing and 22 had been injured from the ravages of the storm and subsequent flooding. Gustav struck the island of Hispaniola, shared by the Dominican Republic and Haiti, as a Category One hurricane on Tuesday. Eight people were killed by the storm in the Dominican, officials said. Thursday, thousands of Haitians were still in emergency shelters, receiving government and NGO aid. The storm destroyed untold numbers of homes, bridges and other structures after floodwaters inundated entire villages in Haiti. Jamaican Prime Minister Bruce Golding said as many as 11 people were believed dead as a result of the storm, as officials said the death toll could rise. "There are regions affected by the storm that our teams have not been able to reach," civil protection director Alta Jean-Baptiste told reporters in Port-au-Prince, adding that most of the deaths occurred in Haiti's southeast. "The majority of victims died when their houses collapsed, or were killed by falling trees. Others drowned when they tried to cross swollen rivers," she said. In the Dominican Republic, Gustav left a wide swath of destruction, forcing more than 6,000 to abandon their homes, local authorities said. British oil group BP, US ConocoPhillips and Anglo-Dutch Shell on Thursday evacuated workers from their energy installations in the Gulf of Mexico, as Gustav loomed. ExxonMobil said it was preparing for the storm and "identifying personnel for possible evacuation to shore." About a quarter of US crude oil installations are located in the Gulf of Mexico. Oil prices fell sharply Thursday, however, as traders discounted the threat of the storm. Meanwhile Tropical Storm Hanna was churning north-northeast of the northern Leeward Islands, and could become a hurricane in a few days, the NHC said.