MIAMI — Authorities sent an aircraft carrier and other Navy ships to help with search-and-rescue operations in Florida on Monday as a flyover of the hurricane-battered Keys yielded what the governor said were scenes of devastation.

“I just hope everyone survived,” Gov. Rick Scott said.

He said boats were cast ashore, water, sewers and electricity were knocked out, and “I don’t think I saw one trailer park where almost everything wasn’t overturned.” Authorities also struggled to clear the single highway connecting the string of islands to the mainland.

The Keys felt Irma’s full fury when the storm blew ashore as a Category 4 hurricane Sunday morning with 130 mph (209 kph) winds. How many people in the dangerously exposed, low-lying islands defied evacuation orders and stayed behind was unclear.

As Irma weakened into a tropical storm and finally left Florida on Monday after a run up the entire 400-mile length of the state, the full scale of its destruction was still unknown, in part because of cutoff communications and blocked roads.

Six deaths in Florida have been blamed on Irma, along with three in Georgia and one in South Carolina. At least 35 people were killed in the Caribbean.

Statewide, an estimated 13 million people, or two-thirds of Florida’s population, remained without power. That’s more than the population of New York and Los Angeles combined. Officials warned it could take weeks for electricity to be restored to everyone.

More than 180,000 people huddled in shelters in the Sunshine State.

“How are we going to survive from here?” asked Gwen Bush, who waded through thigh-deep floodwaters outside her central Florida home to reach National Guard rescuers and get a ride to a shelter. “What’s going to happen now? I just don’t know.”

The governor said it was way too early to put a dollar estimate on the damage.

During its march up Florida’s west coast, Irma swamped homes, uprooted trees, flooded streets, snapped miles of power lines and toppled construction cranes.

In a parting shot, it triggered severe flooding around Jacksonville in the state’s northeastern corner. It also spread misery into Georgia and South Carolina as it moved inland with winds at 50 mph, causing flooding and power outages.