Orlando Smith, premier of the British Virgin Islands, said the situation was "critical" as he asked for immediate aid from the British government.
There are just under 500 troops now in the region, made up of marines, engineers, medics and specialists, including Army and RAF personnel.
Duncan did not say how many prisoners were captured or how many were still loose. A night-time curfew was imposed.
More than 700 troops and 50 police officers have already been sent to the British Virgin Islands after they were battered by the most powerful storm ever recorded in the Atlantic Ocean.
While only preliminary estimates are in of the extent of Irma's devastation, officials told the New York Times that 80 to 90 percent of the buildings were destroyed on Antigua, Babuda, Anguilla, St. Martin and St. Barthelemy. "This story is about the tens of thousands of people who have lost their homes and their livelihoods".
"I think a lot more should be done from us worldwide to help them out".
Prime Minister Gaston Browne said Barbuda was a "scene of total carnage".
"But we love it, and we want to go out and rebuild eventually". The tiny island of Barbuda was nearly completely flattened-locals evacuated and returned to over $100 million in property damage, a huge sum for such a small nation as Antigua and Barbuda. When it first hit Florida, it was still a Category 4 hurricane. The hurricane's storm surge topped Malecon, the iconic seaside boulevard in the capital of Havana. In Miami, hurricane-force winds brought down two cranes. She also said that the leaves could have been dried out by salt that was whipped onto the island when the storm hit. The hurricane caused water levels to rise and fall much quicker than normal, leaving some animals, like this manatee, behind to die on land.
Cubans wade through flooded streets in Havana on September 10, 2017 after being battered by Hurricane Irma.
Navy personnel distributing supplies in Saint Martin
Early estimates suggest a quarter of homes in Florida Keys, where Irma first made landfall in the USA, were destroyed. Weather forecasters believe Jose could still pose a threat to the continental US. Irma's overall death toll is estimated to be at least 40.
The UK has committed £32m to helping overseas territories devastated by Irma. The US Virgin Islands were also badly affected.
Critics have said the UK Government did not prepare adequately, was slow to respond once Irma hit and did less to evacuate its citizens than other nations.
Facts and figures on the United Kingdom government's relief work in the Caribbean and the British Overseas Territories in response to Hurricane Irma.
Ms Knight, originally from Dorset, has lived on the island for the past four years with Mr Whitting and the couple have a two-year-old daughter, Dottie. "I will shake up all the rules and procedures so the job is done as quickly as possible".
Foreign Secretary Boris Johnson on Monday defended Britain's response to an "unprecedented catastrophe".
French President Emmanuel Macron is due to visit St. Martin on Tuesday.
Despite sending reinforcements and ships to deliver help, France, Britain and the Netherlands have been criticized for not doing enough for the islands that they oversee.