As Hurricane Dorian accelerates up the Florida coast, the magnitude of the storm's destruction in the Bahamas is coming into view. Parts of the island nation are in ruins. Much of Grand Bahama Island is underwater.

Two more deaths were confirmed overnight, bringing the official total now to seven. The country's prime minister said he expects that number to rise.

The extent of Dorian's destruction across the Northern Bahamas is immense. As seen from the air over Abaco Island, the damage stretches for miles.

Entire neighborhoods are flattened, homes shredded, shipping containers and boats hurled inland. Some airports now look more like lakes. The terminal of one airport is now shrouded in debris.

An aerial view shows devastation after Hurricane Dorian hit the Abaco Islands in the Bahamas, September 3, 2019, in this image obtained via social media. Michelle Cove/Trans Island Airways/via Reuters

"We are in the midst of one of the greatest national crises in our country's history," said Prime Minister Hubert Minis. "It is going to require a massive coordinated effort to rebuild."

Dorian pummeled Abaco and Grand Bahama Islands for two days, with 30 inches of rain and a storm surge as high as 23 feet.

The Red Cross says more than 13,000 homes – nearly half the number on those two islands – were damaged or destroyed.

An aerial view of the devastation in the Bahamas. Brandon Clements/Bret Adair/LSM

Video from inside one home during the storm shows waves crashing against a second-story window, as more water poured in from below, pounding against the stairs. Dorian largely spared Nassau, the island nation's capital, and so its airport is now home to a major relief effort to help other islands to the north, like hard-hit Abaco Island.

The prime minister flew over Abaco yesterday, and said he saw 30 stranded people waving yellow flags in distress before a helicopter was dispatched to rescue them.

Lead national correspondent David Begnaud, reporting from Nassau, said there are local reports of more deaths and scores missing.

The U.S. Coast Guard says it has rescued more than 45 people after deploying several helicopters to the region. "At this point, we are still in the very early stages of the response," Coast Guard Captain Shawn Koch said. "We are concentrating very much on parts, fuel, people, [and] communications gear."

The slow-moving storm, mixed with the crippled infrastructure, has delayed search and rescue efforts, leaving many people to fend for themselves.

Tim Aylen, a journalist working with the Associated Press, filmed himself and his family abandoning their Freeport home. His daughter waded through the life-threatening storm surge carrying one of their pets.

Associated Press journalist Tim Aylen's family evacuated with their pets from their home in Freeport. Tim Aylen

People are using boats, jet-skis, even inflatable toys to help ferry others to safety.

"It came over the roof; I would imagine 21 feet at least," Howard Armstrong told CNN. He described the gut-wrenching moment water flooded his home – and his wife died in front of him.

"She was standing on top of the kitchen cabinets until they disintegrated. And I kept with her, and then she just drowned on me." Armstrong said he got out of his home and swam to his nearby boat for safety.

Rescue efforts in the Bahama Islands. CBS News

Prime Minister Minis said the government is sending police to the island to address concerns about safety.

A Royal Navy vessel which arrived overnight will help deliver food to the Abaco Islands. Famed chef Jose Andres, who is there with his organization World Central Kitchen, is preparing to deliver thousands of meals today to Abaco and Grand Bahama Islands.

Dorian is moving north Wednesday as a strong category 2 storm, hugging the U.S. coastline. Hurricane warnings are up along the coast in north Florida and in the Carolinas.

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