At least 19 people have died in Jamaica as a result of Hurricane Melissa, Information Minister Dana Morris Dixon has said, as search and rescue efforts continue and authorities try to get aid to hard-hit areas.

The hurricane, one of the most powerful to strike the Caribbean, has also killed at least 30 people in Haiti, officials said.

In Jamaica, there are entire communities that seem to be marooned and areas that seem to be flattened, Dixon said, adding there are devastating scenes in western regions.

Electricity remains out to most of the island and as people try to salvage damaged homes and belongings from floodwaters and mud, many thousands are growing increasingly desperate for aid.

There are parts of the country that have been without water for several days and food is growing increasingly scarce.

Aid supplies are starting to arrive more rapidly with the main airport in the Jamaican capital, Kingston, largely back to normal. But smaller regional airports, some of which are located near to where humanitarian assistance is most needed, remain only partly operational.

As such, aid agencies and the military are bringing in the urgently needed supplies from Kingston via road, many of which remain unpassable in places.

Satellite imagery shows nearly all buildings in some Jamaican villages have been destroyed by the hurricane.

Residents of towns in western Jamaica told the BBC on Thursday that words can't explain how devastating the storm has been on the country.

In Haiti, many victims in the storm died when a river overflowed in Petit-Goave, and a full assessment is ongoing.

In Cuba, more than 3 million people were exposed to life-threatening conditions during the hurricane, but no fatalities had been reported at the time of the storm's impact.

The hurricane made landfall on Tuesday as a category five storm, packing winds of up to 185 mph (295 km/h), before impacting other countries in the Caribbean.

Global support is mobilizing, with the U.S. deploying disaster response teams and the UK sending additional humanitarian supplies.

Meanwhile, Bermuda is preparing for Melissa, expected to hit as a category two hurricane.