Hurricane Irma causes widespread damage on Caribbean Islands

France sent emergency food and water rations to the French islands of Saint Martin and Saint Barthelemy, where Irma ripped off roofs and knocked out all electricity.

Dutch marines who flew to three Dutch islands hammered by Irma reported extensive damage but no deaths or injuries.

While France received no immediate reports of casualties, the minister for French overseas territories, Annick Girardin, said: "We have a lot to fear for a certain number of our compatriots who unfortunately didn't want to listen to the protection measures and go to more secure sites... We're preparing for the worst."

By early Wednesday afternoon the centre of the storm was 20 miles east-south-east of St Thomas in the US Virgin Islands and 90 miles east of San Juan, Puerto Rico and heading west-north-west at 16 mph.

The US National Weather Service said Puerto Rico had not seen a hurricane of Irma's magnitude since Hurricane San Felipe in 1928, which killed a total of 2,748 people in Guadeloupe, Puerto Rico and Florida.

"The dangerousness of this event is like nothing we've ever seen," Puerto Rico Governor Ricardo Rossello said.

"I'm scared...I don't want to be here." Florida residents evacuate ahead of Category 5 Hurricane Irma https://t.co/2I5eLhnKXX pic.twitter.com/ZMKp7WcJ5m

— CBS News (@CBSNews) September 6, 2017

"A lot of infrastructure won't be able to withstand this kind of force."

Puerto Rico's public power company has cut back on staff and maintenance amid a deep economic crisis and the agency's director warned that some areas could be without power from four to six months because the infrastructure has already deteriorated so badly.

Power outages were reported in some neighbourhoods well ahead of the storm.

The US government has stepped in, with President Donald Trump this week approving an emergency declaration for the US Virgin Islands and Puerto Rico.

That means that the Federal Emergency Management Agency and other agencies can remove debris and give other services that will largely be paid for by the US government.

The US National Hurricane Centre said Irma's winds would fluctuate, but the storm would likely remain at Category 4 or 5 for the next day or two as it roared past Puerto Rico, the Dominican Republic, Haiti, Cuba, the Turks & Caicos and parts of the Bahamas.

Intense video shows NOAA Hurricane Hunters flying through the eye of Hurricane #Irma. https://t.co/unLLI5UNmM pic.twitter.com/qlLBCXZKn6

— ABC News (@ABC) September 6, 2017

By early Sunday, Irma is expected to hit Florida, where Governor Rick Scott said he planned to activate 7,000 National Guard members by Friday and warned that Irma is "bigger, faster and stronger" than Hurricane Andrew.

Andrew pummelled south Florida 25 years ago and wiped out entire neighbourhoods with ferocious winds.

Mr Trump also declared an emergency in Florida and authorities in the Bahamas said they would evacuate six southern islands.

National Weather Service director Louis Uccellini said he was concerned about Florida up the east coast to North Carolina, starting with the Florida Keys.

"We're very worried about the impact of the winds and surge on the Keys as the storm approaches," Mr Uccellini said.

"Be ready for all the hazards associated with this storm (storm surge, high winds and heavy rain). They are all going to be dangerous."

Floridians stocked up on drinking water and other officials in the Florida Keys geared up to get tourists and residents out of Irma's path.

The mayor of Miami-Dade County said people should be prepared to evacuate Miami Beach and most coastal areas as soon as Wednesday evening.

Hurricane #Irma batters Caribbean, Florida braces for landfall. Follow @Reuters live blog for the latest: https://t.co/Gy2bC4BWzc pic.twitter.com/5HxTYMvg8D

— Reuters (@Reuters) September 6, 2017

He activated the emergency operation centre and urged residents to have three days' worth of food and water.

MIT meteorology professor Kerry Emanuel, an expert in hurricanes, calculated that the amount of energy in Hurricane Irma is about seven trillion watts, about twice the energy of all bombs used in the Second World War.

Warm water is fuel for hurricanes and Irma was moving over water that was 1C warmer than normal.

The 26C water that hurricanes need went about 250 feet deep, said Jeff Masters, meteorology director of the private forecasting service Weather Underground.

Four other storms have had winds as strong in the overall Atlantic region, but they were in the Caribbean Sea or the Gulf of Mexico, which usually have warmer waters.

Hurricane Allen hit 190 mph in 1980, while 2005's Wilma, 1988's Gilbert and a 1935 great Florida Keys storm all had 185 mph winds.

Bahamas Prime Minister Hubert Minnis said his government was evacuating six islands because authorities would not be able to help anyone caught in the "potentially catastrophic" wind, flooding and storm surge.

People there would be flown to Nassau in what he called the largest storm evacuation in the country's history.

The northern parts of the Dominican Republic and Haiti could see 10 inches of rain, with as much as 20 inches in the south-east Bahamas and Turks and Caicos.

Also on Wednesday, a new tropical storm formed in the Gulf of Mexico off Mexico's coast.

Tropical Storm Katia had maximum sustained winds of 45 mph by the early afternoon and the hurricane centre said it could become a hurricane before it approaches the coast of Veracruz state.

Katia was located about 175 miles north of the city of Veracruz.

And another tropical storm farther east in the Atlantic was expected to become a hurricane by Wednesday night.

Tropical Storm Jose's maximum sustained winds had increased to near 70 mph.

The storm was centred about 1,135 miles east of the Lesser Antilles and was moving west at 13 mph.

AP