The Dutch interior ministry confirmed that the prison at Point Blanche, which has about 130 prisoners, had been badly damaged by Irma, but said Dutch troops were quickly sent to guard it.
Irma hit battered central Cuba on Saturday, knocking down power lines, uprooting trees and ripping off roofs.
By Saturday evening, the sea had penetrated two blocks over parts of the city's historic seafront boulevard, and the waters were expected to advance farther as the surge grew. But with state salaries of about $25 a month and government agencies strapped for cash, most buildings have seen little maintenance in decades.
About 70 percent of the beds at the main hospital in the French portion of St. Martin were severely damaged, and more than 100 people needing urgent medical care were evacuated.
"It was our first experience of a hurricane, which we don't have at home".
With organization, discipline and the integration of all our structures, we will get through as we have done on previous occasions.
Hurricane Irma, with its destructive force, stormed our Island for more than 72 hours, from the morning of September 8 to the afternoon of this Sunday.
Macron said 11 people were killed in the French side of St. Martin, up from a previous death toll of 10. We should not delude ourselves, the task ahead of us is vast, but with a people like ours, we will win the most important battle: recovery. The strength of the storm is expected to remain a tropical storm for the next three days, but the size is unknown.
Witnesses said a provincial museum near the eye of the storm was in ruins.
The state meteorological service INSMET reported that the waves were up to seven meters (23 feet) on the northern coast.
Contacted by AFP, the foreign ministry declined to comment.
A string of small Caribbean islands was left reeling by Irma.
"Sheets of zinc that came flying into our backyard also damaged the kitchen wall and we lost many roof tiles", said Angel Coya, 52, adding he was optimistic that Cuba's Communist government would help fix the damage. Prime Minister Gaston Browne described the result as "total devastation". (AAP) Army Commandos deliver aid and provide support to British Virgin Islands communities on the island of Tortola.
MARTIN: Were any of these islands evacuated?
It said two members of the United Kingdom police cadre, who support the military in times of global crisis, flew out on Friday, while a further 53 British officers from 14 police forces, including the Metropolitan Police, are due to leave from RAF Brize Norton in co-operation with the MoD.
The huge winds caused massive damage to homes and businesses on the southern tip of Florida.
"People don't realise that these are British people, these are British islanders and we have a duty to them".
Some of the damage to The British Virgin Islands.
MARTIN: Can you give us a sense of how extensive the damage is in Cuba?
The Facebook group BVI Abroad - Hurricane Irma already has 20,000 members and Turnbull said the group has been the best resource to keep people updated. "I am truly heartbroken by this news". Las Tunas was hit by strong winds and persistent, intense rains. Islands like Barbuda, Haiti, Puerto Rico and the Dominican Republic are in ruins. Many were desperate to get news of their families in Florida who also faced Irma and to tell them how they had fared.
CNN's Patrick Oppmann reported from Caibarien and Lauren Said-Moorhouse and Laura Smith-Spark wrote from London.