The confirmed death toll across the southern United States from the impacts of Hurricane Helene has climbed to 130, making it one of the deadliest hurricanes to hit the US this century.

Hundreds of people are still reported missing, though cell service is poor and many could be without a way to communicate. On Tuesday (local time), about 1.6 million electric customers had no power in Florida, Georgia, the Carolinas and Virginia, according to poweroutage.us.

In vast areas of the southeast, roads remain inaccessible and communication systems battered. Despite a surge of relief supplies from state and federal agencies, many residents remain desperate for water, food, medicine and medical care. With trees blocking roads, bridges out, gasoline scarce and information spotty, the rescue and recovery process has been painfully slow in places.

“We’re just really suffering and just hampered and hurting by the lack of communication,” said Larry Greene, a senior hospice chaplain for Hospice and Home Care of the Blue Ridge. “We have very sick, dying patients who need help, from young children to people with cancer in their 40s. But a majority are elderly patients. We are just looking at these totally nonexistent roads.”

The worst flash floods occurred in western North Carolina, where rain measuring in feet fell on steep mountain slopes that funnelled the water into communities and homes along rivers and creeks. The water rose so quickly that many residents were caught off guard.

Horrifying stories of people swept away by floodwaters have been steadily emerging as survivors finally make contact with friends and family members.

“My mom, sister and brother-in-law had to just jump into the rushing water and they had to watch all their animals die,” said Amber Leverette Anderson, 41, of Banner Elk, North Carolina. Among the deceased was the family dog, Storm, so named because she was so helpful in smaller floods, and her new litter of puppies.

“But we are also lucky because people are finding their family members’ bodies. We are blessed to be alive,” Anderson said. The family home in Spruce Pine is “totally gone”, she said. “Just crushed. It’s been our family house since the 1920s.”

She said a close friend found a note at the house, written by her mother, saying they were safe at a motel. “They have no shoes. They are still in the clothes they swam in. The motel has no running water for showers.”

The sheriff’s office in Macon County, North Carolina, posted on Facebook “one of the most difficult releases we have ever had to make”. An emergency call Friday reported a truck in the river, with a driver inside it.

“Officials soon made the grave realisation that the truck matched the description of one of their own: Jim Lau, a courthouse security officer.” The statement asked for prayers for Lau’s family and loved ones. “Continue to pray for Western North Carolina as a whole; the tragedy that surrounds our mountain communities is unimaginable.”

Asheville, North Carolina, Mayor Esther Manheimer said on CNN late on Monday that 600 residents remain unaccounted for and that reaching them is the priority. “But we also are in a situation where we don’t have water and power in most areas, and we do need resources like drinking water and food and other household supplies and personal supplies people might need,” she said.

Officials at all levels said the rising death toll remained fluid, with few willing to guess at where the total would stop. State officials in North Carolina, for example, said Tuesday that 38 people had died in the storm. But in Buncombe County alone, officials put the tally at 50 dead.

South Carolina’s toll ticked upward to 36, with 25 confirmed dead in Georgia, 11 in Florida, six in Tennessee and two in Virginia.

Lillian Govus, Buncombe County’s director of communications, said search-and-rescue crews are combing through isolated areas and knocking on doors. On Tuesday, the county sent a text blast out to every person still unaccounted for. “The unaccounted number is really hard for us to share with any confidence because it changes so fluidly,” she said.

North Carolina Governor Roy Cooper said 92 teams are conducting search-and-rescue operations in the mountains.

“Communities were wiped off the map,” Cooper said.

Will Ray, the state’s head of emergency management, said that “this disaster is unlike anything our state has ever experienced”.

The National Guard has rescued about 500 people so far, said North Carolina Adjutant General Todd Hunt, and delivered food and supplies to the Asheville airport. CH-47 Chinook helicopters are flying into places inaccessible by road.

North Carolina Attorney General Josh Stein said his office has received 70 complaints of businesses trying to gouge vulnerable people with high prices for fuel, groceries and hotel rooms.

As the scale of the damage and the death toll became clear, former president Donald Trump flew to the southern Georgia city of Valdosta and, attempting to leverage the catastrophe, criticised the Biden administration’s response. Georgia and North Carolina are among the handful of battleground states whose outcomes will determine the presidential election.

Trump falsely claimed that Georgia Governor Brian Kemp had not been able to speak to President Joe Biden. Kemp said that was not true.

“[The president] just said, ‘Hey, what do you need?’ And I told him, you know, we got what we need,” Kemp said days ago. “We’ll work through the federal process. He offered and if there’s other things you need, just to call him back directly, which, I appreciate that.”

Biden said of Trump: “He’s lying, and the governor told him he was lying.”

Both Biden and Vice-President Kamala Harris announced plans to visit the storm zone. Biden plans to visit the Carolinas, including an aerial tour of the flooded areas and meetings with first responders and state and local officials. Harris planned a visit to Georgia, and her office said she had talked with several governors and mayors in affected areas.

Biden and Harris have emphasised that thousands of federal workers are already assisting in rescue and recovery efforts. Federal Emergency Management Agency (FEMA) administrator Deanne Criswell said that she and the federal government will remain in western North Carolina until the crisis is over.

At a White House briefing, Homeland Security Secretary Alejandro Mayorkas outlined the federal response, which officials said included 1200 search-and-rescue personnel, another 2000 federal workers performing other duties and 1300 FEMA workers.

Mayorkas said that the Helene recovery effort would be a “multibillion-dollar undertaking” and that rebuilding will be “extraordinarily costly”.

White House press secretary Karine Jean-Pierre said FEMA had shipped 7.1 million meals and more than 7.5 million litres of water, as well as other supplies. The Defence Department has moved in 30 high-water trucks and 22 helicopters, she said, and Pentagon spokesman Major General Patrick Ryder said about 6500 personnel are now involved in Helene relief efforts.

The most brutal effects of Helene came not from wind or storm surge but from rain hundreds of miles inland, in the high country. The storm made landfall Thursday as a Category 4 hurricane in Florida’s sparsely populated Big Bend region southeast of Tallahassee.

It then raced north with unusual speed, and by Friday morning emergency bulletins went out to cellphones in western North Carolina warning of life-threatening flash flooding. Rain fell in an area already saturated from another tropical system centred off the Atlantic seaboard in recent days.

Some communities received close to 30 inches of rain over just a few days, sending river levels to record flood stages.

There are recent precedents for such storms – but not for so great a loss of life. Tropical Storm Irene in 2011 caused severe flash floods in Vermont and Upstate New York. And in 2018, Hurricane Florence’s slow progress across the Carolinas led to historic long-duration flooding.

The effects of the hurricane have been felt over a huge region. At least 425 roads were closed because of damage in at least 700 places in North Carolina, according to Joey Hopkins, the state’s transportation secretary. Officials have prioritised highways such as Interstate 40, which partially reopened near Asheville, and roads that serve hospitals and emergency services. As those start to open, work will shift to smaller streets where many residents remain trapped behind debris.

“They weren’t getting any linemen or arborists into those areas until the roads were rebuilt, so we couldn’t even really assess the damage,” said Lucas Beane, chief operations officer for Lucas Tree Experts, which has about 100 employees working to clear fallen trees in the Carolinas.

One of the precious commodities right now is gasoline. In Watkinsville, Georgia, retired military officer Dwight Townsend was filling up five five-gallon gas tanks at a gas station to take back to his home nearly 100 miles away in Evans, Georgia.

“The destruction is unbelievable,” he said. “The area looks like a war zone.”

He was heading back with the gas and two generators for his household and for a neighbour who is diabetic and desperately needs refrigeration for medicine.