KINGSTON Jamaicans snapped up emergency supplies as Hurricane Dean bore down on their Caribbean island, threatening to become a rare Category 5 storm when it later nears Mexico's Yucatan and the oil rigs of the Gulf of Mexico.
The first hurricane of what is expected to be an above-average 2007 Atlantic storm season has already pounded the eastern Caribbean, where it killed at least three people.
It was blamed for three more deaths on Saturday as millions went on alert in some of the most populous areas of the Caribbean including Haiti, the Dominican Republic, Cuba and all of mountainous Jamaica.
With sustained winds of 150 mph (240 km per hour), Dean was a Category 4 storm, the second-highest level on the five-step Saffir-Simpson scale. It was expected to smash into Jamaica on Sunday.
It could become a Category 5 storm within two days, with sustained winds of more than 155 mph (250 kph).
Just before 5 p.m. EDT, Dean was located 455 miles east-southeast of Kingston and about 165 miles
south of Santo Domingo. It was moving west-northwest at 18 mph (30 kph), the U.S. National Hurricane Center said.
Jamaica's government urged people to flee low-lying and landslide-prone areas, buses were marshaled to transport evacuees and police and troops were put on alert.
Lines formed at gas stations and supermarket aisles were crammed as shoppers bought batteries, flashlights, canned tuna, rice and bottled water.
"I am prepared, but I still want the storm to change direction," said a man in one store who did not give his name.
Campaigning for August 27 national elections was halted.
"The country is on high alert," said Kerry-Ann Morris, a spokeswoman for Jamaica's disaster preparedness office.
Three people died in the Dominican Republic, where the hurricane sent 18-foot (5.5-meter) waves crashing onto southern beaches.
One of the dead was a 16-year-old Haitian swept out to sea. The others were crushed when their tin-and-wood hut collapsed under the wind and rain, officials said.
Dean's progress was being watched closely by energy markets, skittish since powerful storms in 2004 and 2005 swept through the Gulf of Mexico where roughly a third of U.S. domestic crude is produced. At least one production platform and two oil rigs were evacuated.
The latest computer models showed Dean hitting the northern Yucatan Peninsula on Tuesday before emerging in the Gulf, where it could go through the Cantarell Complex of Mexican oil fields, one of the world's most productive.
Most models had the storm hitting north Mexico after that, but one took it ashore in south Texas.
Mexican authorities began evacuations on the Caribbean coast, moving 2,500 people from the island of Holbox. U.S. President George W. Bush issued an emergency declaration for Texas to free up federal help and funds.
Dean's destructive core was expected to spare Haiti's south coast. But tropical cyclones frequently trigger flash floods and mudslides in the deforested, poverty-stricken country of 8 million people. A brush with Tropical Storm Jeanne in 2004 killed nearly 3,000.
Dean trampled Martinique, St. Lucia and Dominica on Friday, triggering landslides, lifting roofs off houses and knocking out power.
The Caribbean Disaster Emergency Response Agency reported three people were killed in Dominica and St. Lucia.
French authorities said two elderly people died during the storm on Martinique, one of a heart attack.
Dean destroyed all of Martinique's banana crop and 70 percent of its sugar cane. Around 80 percent of the banana plantations in nearby Guadeloupe were also destroyed, causing $161 million in losses there.
Category 5 hurricanes are rare. Until the record-breaking 2005 Atlantic hurricane season, records showed only two years -- 1960 and 1961 -- with more than one Category 5 storm.
But in 2005, four hurricanes reached that strength -- Emily, Katrina, Rita and Wilma -- triggering debate about the impact of global warming on tropical cyclones.
(Additional reporting by Jim Loney, Michael Christie and Jane Sutton in Miami, Manuel Jimenez in the Dominican Republic, Shurna Robbins in the Cayman Islands, Carlos Barria in Kingston and Anna Willard in Paris)