A bridge collapsed into a river swollen by Hurricane Dennis' fierce winds and rain, killing at least four people in south-western Haiti on Thursday local time as the strengthening storm lashed Caribbean coastlines.

The hurricane's winds neared 216 kph, and it grew to a Category 4 as it sideswiped Jamaica and headed straight for Cuba. Forecasters at the US Hurricane Centre in Miami predicted the storm could hit the United States anywhere from Florida to Louisiana by Sunday or Monday, raising fears that oil production in the Gulf of Mexico would be disrupted by the fourth storm in as many weeks.

Thunderstorms covered the Dominican Republic, southern Haiti and northeast Jamaica. The Cayman Islands and Cuba were under hurricane warnings, including the US detention camp at Guantanamo Bay holding some 520 terror suspects.

In the southwestern Haitian town of Grand Goave, a reporter saw at least four people killed after the wood and metal bridge collapsed. Witnesses said the river came suddenly rushing over the bridge.

Elsewhere on the dangerously deforested island, wind gusts uprooted a palm tree and flung it into a mud hut, killing a fifth person in the southern town of Les Cayes, the Red Cross said.

The Florida Keys were under a hurricane warning on Thursday and ordered tourists to evacuate, and the southern Florida peninsula was on tropical storm watch, expecting severe conditions within 36 hours.

In Jamaica, Prime Minister Percival Patterson urged people in low-lying areas to evacuate.

"Let us all work together in unity so that we will be spared the worst," Patterson said in a national radio broadcast. Despite his appeal, only about 1,000 people were in shelters late afternoon.

This is a "dangerous hurricane" that could strengthen considerably by early on Friday, the hurricane centre warned.

The hurricane centre warned the eye could pass over central Cuba sometime Friday afternoon.

Source: China Daily