Media playback is unsupported on your device Media caption "The wind was like nothing I've ever known in my life"

The UK is stepping up its relief effort in response to Hurricane Irma, with the first of three RAF aid flights on its way to the Caribbean.

A Royal Fleet Auxiliary ship has also begun delivering emergency aid to British overseas territory islands hit by the disaster.

Houses have been reduced to rubble in the British Virgin islands, where a state of emergency has been declared.

The UK government has been accused of responding too slowly to the storm.

The British Virgin Islands' governor, Gus Jaspert, has asked the UK for help amid reports of widespread devastation, with casualties and fatalities reported.

Mr Jaspert has warned that another storm, Hurricane Jose could reach the islands at the weekend.

Sharon Flax-Brutus, director of tourism for the British Virgin Islands (BVI), said the damage was difficult to assess because communications were down, but that "many homes are without roofs, or have been diminished to merely foundations".

Image copyright AFP PHOTO / HUBERT HACISKI Image caption A state of emergency has been declared in the BVI which was hit by Hurricane Irma

Simon Cross, who moved to the BVI two years ago, said the first warning he had of the hurricane hitting his building was when a skylight was blown off the roof.

"The wind was scary enough for us to all end up huddling in an adjoining bathroom which had a small window protected by metal shutters.

"The wind was like nothing I've ever known in my life. It was crazy."

Briton Emily Killhoury, who lives on Tortola in the BVI with her husband Michael and their two children, aged nine and 10, told the BBC her family bunkered down in a cupboard when the storm hit.

"Our downstairs doors suddenly blew out, which was terrifying. We just stayed hiding," she said.

"We eventually emerged at about 7pm to see total devastation. Everybody is shocked, but trying to be practical."

Image copyright Emily Killhoury Image caption Emily Killhoury's house was a strong concrete structure, other properties were worse hit

Sir Richard Branson, who was at his private retreat on Necker Island in the BVI, said the whole area had been "completely and utterly devastated".

In a blog, Sir Richard said his team were safe and well after taking shelter in his concrete wine cellar, but added: "I've never seen anything like this hurricane.

"We are still assessing the damage, but whole houses and trees have disappeared."

Irma passed over the British overseas territories of Anguilla, Montserrat and the BVI on Wednesday night - and went on to batter another, the Turks and Caicos islands further north, on Thursday evening.

Image copyright Claire Mays Image caption Ex-pat Pheadra McLellan, left, lives on St Martin with her three children and French partner

There have also been concerns for British nationals who are living in areas outside the overseas territories.

British national Pheadra McLellan, her three children and her French partner Bernadine Gallis live on the island of St Martin.

Ms McLellan's family last spoke to her on Wednesday night, when she said the family were seeing the storm out in a bedroom in their house.

Cousin-in-law Claire Mays said: "[We've] been calling the consulate, the FCO, but we've just been told, 'OK you've given us their details, please update us once you hear from them so we can tick it off the list.'"

The storm is now expected to hit Florida or neighbouring states in the US over the weekend.

Image copyright MOD Image caption UK armed forces assessing the damage in Anguilla on Thursday

The UK has almost tripled the relief fund for British overseas territories to £32m, amid criticism of its response.

Prime Minister Theresa May has chaired a meeting of the government's emergency response Cobra committee.

She said UK troops deployed on the Royal Fleet Auxiliary (RFA) ship Mounts Bay have been working in Anguilla and have "made the airfield serviceable, restored power to the hospital and rebuilt emergency shelters".

They have also begun assisting the governor of the BVI and working to ensure the airfield is accessible for military aircraft to fly in with emergency supplies, she added.

"Every effort is being made to ensure that as much as possible can be done in advance of Hurricane Jose, which is the next hurricane reaching that area."

The prime minister said the UK was also "committed" to providing support to ensure reconstruction work is done in the region in the long-term.

British overseas territories are self-governing but rely on the UK for protection from natural disasters.

Labour leader Jeremy Corbyn said the impact of Hurricane Irma on the Caribbean was "entirely predictable" and the British government "should have acted much faster".

But Mrs May has insisted that the UK responded "swiftly".

What has happened in British territories?

Anguilla: Hit by the full blast of the hurricane on Wednesday. At least one death reported.

Hit by the full blast of the hurricane on Wednesday. At least one death reported. British Virgin Islands: Reports of casualties and fatalities and extensive damage. Expected to require extensive humanitarian assistance. In a message the people of the BVI, governor Gus Jaspert said: "I come to you with a heavy heart after experiencing and observing the extent of devastation caused by Hurricane Irma." Communications are difficult.

Reports of casualties and fatalities and extensive damage. Expected to require extensive humanitarian assistance. In a message the people of the BVI, governor Gus Jaspert said: "I come to you with a heavy heart after experiencing and observing the extent of devastation caused by Hurricane Irma." Communications are difficult. Montserrat: "Swiped" by Irma but suffered less serious damage.

"Swiped" by Irma but suffered less serious damage. Turks and Caicos: Battered by the hurricane on Thursday night, with roofs ripped off, streets flooded, utility poles snapped and a widespread black-out on the main island of Grand Turk.

What is the UK doing?

Image copyright MOD Image caption A British Royal Logistics Corps Mexflote arrives in Anguilla to help with the relief effort

Humanitarian workers with 200 shelter kits and the British ship, RFA Mounts Bay, were sent to the area before the hurricane struck.

The MoD-owned vessel arrived in Anguilla on Thursday and delivered six tonnes of emergency aid, with personnel there clearing roads and helping to restore power.

The ship has since arrived in the BVI - 90 miles to the west - to help with disaster relief efforts there.

Warship HMS Ocean is also being sent from the Mediterranean but is not expected to arrive for another two weeks.

The first British military flight to join the relief effort has left RAF Brize Norton in Oxfordshire carrying about 50 personnel - including engineers, marines and medics, as well as rations and water.

Other transport aircraft are expected to follow with helicopters on board.

What is the advice for travellers?

Thousands of British tourists are believed to be holidaying in the Caribbean, the travel association Abta said.

Britons in the region have been urged to follow evacuation orders, while states of emergency have been declared in Puerto Rico, Cuba and Florida, amid fears Miami could be struck directly by the hurricane.

Holiday firms are monitoring the situation and some have cancelled flights or offered to amend bookings for those due to travel to affected areas in the coming days.

The cruise company Carnival has cancelled four cruises bound for the Caribbean that were due to depart over the next few days - and warned that others may be cut short.

The Foreign Office urges people planning to go to the areas to follow the advice from the local authorities, including any evacuation orders, and check its official travel guidance before travelling.

It has set up a hotline for people affected by the disaster and for people whose loved ones may be affected on 020 7008 0000.

Do you have family members living in one of the British Overseas Territories affected by the hurricane? Have you been in contact with them? Share your experiences by emailing haveyoursay@bbc.co.uk.

Please include a contact number if you are willing to speak to a BBC journalist. You can also contact us in the following ways: