PERRY, Fla. (AP) — Gov. Roy Cooper said Sunday that the death toll of 11 in North Carolina is expected to rise from Hurricane Helene as rescuers and other emergency workers reach areas currently isolated by collapsed roads, failing infrastructure and widespread flooding.

“This is an unprecedented tragedy that requires an unprecedented response,” Cooper said at a press conference Sunday. He added that “we know there will be more” deaths and he asked residents to avoid traveling on roadways in western North Carolina not only to avoid dangers but to keep roads clear for emergency vehicles. More than 50 search teams have fanned out across the region in search of stranded people.

“Many people are cut off because the roads are impassable,” he said. Supplies were being airlifted to the region around Asheville, a city tucked in the western North Carolina mountains known for its arts, culture and natural beauty.

LIVE MAP: Track the path of Hurricane Helene

The rescue efforts included saving 41 people in one mission north of Asheville and an infant. The teams were finding people through both 911 calls and messages on social media, North Carolina Adjutant General Todd Hunt said.

Hurricane Helene roared ashore in Florida’s Big Bend region as a Category 4 hurricane late Thursday with winds of 140 mph (225 kph).

From there, it quickly moved through Georgia, where Gov. Brian Kemp said Saturday that it “looks like a bomb went off” after viewing splintered homes and debris-covered highways from the air. Weakened, Helene then soaked the Carolinas and Tennessee with torrential rains, sending creeks and rivers over their banks and straining dams. More than 60 people have been killed. Several million people were without power as of Sunday afternoon.

In Texas, Jessica Drye Turner begged for someone to rescue her family members stranded on their rooftop in Asheville, surrounded by rising flood waters. “They are watching 18 wheelers and cars floating by,” Turner wrote in an urgent Facebook post on Friday.

But in a follow-up message, which became widely circulated on social media on Saturday, Turner said help had not arrived in time to save her parents, both in their 70s, and her six-year-old nephew. The roof had collapsed and the three drowned.

“I cannot convey in words the sorrow, heartbreak and devastation my sisters and I are going through nor imagine the pain before us,” she wrote.

Western North Carolina was isolated because of landslides and flooding that forced the closure of Interstate 40 and other roads. There have been hundreds of water rescues, none more dramatic than in rural Unicoi County in East Tennessee, where dozens of patients and staff were plucked by helicopter from a hospital rooftop Friday.

The storm was expected to hover over the Tennessee Valley on Saturday and Sunday, the National Hurricane Center said.

It unleashed the worst flooding in a century in North Carolina. One community, Spruce Pine, was doused with over 2 feet (0.6 meters) of rain from Tuesday through Saturday. The death toll in Buncombe County is at 10, and Sheriff Quintin Miller indicated at a Sunday morning media briefing it will likely go higher. He said authorities are struggling to notify families of the dead because the lack of telephone, cellphone and internet.

The state is sending water supplies and other items toward Buncombe County and Asheville, but mudslides on Interstate 40 and other blocked highways are preventing the supplies from making it. The county’s own supplies of water were on the other side of the Swannanoa River, away from where most of the 270,000 people in Buncombe County live, officials said.

Law enforcement was making plans to send officers to places that still had water, food or gas because of reports of arguments and threats of violence, the sheriff said.

“If you will bear with us and be patient one more day — I hate to say that but I know how desperate water is in our community — but we are pushing as hard as we can to get them up the mountain,” Buncombe County Manager Avril Pinder said.

In Florida’s Big Bend, some lost nearly everything they own, emerging from the storm without even a pair of shoes. With sanctuaries still darkened in a county where as of Sunday morning, 97 percent of customers were without power, some churches canceled regular services while others like Faith Baptist Church in Perry opted to worship outside.

WATCH: Florida’s Big Bend region begins lengthy cleanup in the aftermath of Helene’s landfall

Standing water and tree debris still covers the grounds of Faith Baptist Church. The church called on parishioners to come “pray for our community” in a message posted to the congregation’s Facebook page.

“We have power. We don’t have electricity,” parishioner Marie Ruttinger said. “Our God has power. That’s for sure.”

In Atlanta, 11.12 inches (28.24 centimeters) of rain fell over 48 hours, the most the city has seen over two days since record keeping began in 1878.

In Augusta, in eastern Georgia near the border with South Carolina, officials notified residents Sunday morning that water service would be shut off for 24 to 48 hours in the city and surrounding Richmond County. A news release said trash and debris from the storm “blocked our ability to pump water.” Officials were distributing bottled water at the municipal building and said each household would receive one case.

President Joe Biden said Saturday that Helene’s devastation has been “overwhelming” and pledged to send help. He also approved a disaster declaration for North Carolina, making federal funding available for affected individuals. Dozens of utilities crews from New England states were also headed south to help with recovery.

Federal funding will be critically important for rebuilding local communities, Sen. Marco Rubio said during an appearance on NBC’s Meet The Press.

“There are some coastal areas, some of which are now facing their third storm in the last 12 months,” Rubio said.

With at least 25 killed in South Carolina, Helene is the deadliest tropical cyclone for the state since Hurricane Hugo killed 35 people when it came ashore just north of Charleston in 1989. Deaths also have been reported in Florida, Georgia, North Carolina and Virginia.

Moody’s Analytics said it expects $15 billion to $26 billion in property damage. AccuWeather’s preliminary estimate of the total damage and economic loss from Helene in the U.S. is between $95 billion and $110 billion.

Among the 11 confirmed deaths in Florida were nine people who drowned in their homes in a mandatory evacuation area on the Gulf Coast in Pinellas County, Sheriff Bob Gualtieri said.

Climate change has exacerbated conditions that allow such storms to thrive, rapidly intensifying in warming waters and turning into powerful cyclones sometimes in a matter of hours.

Helene was the eighth named storm of the Atlantic hurricane season, which began June 1. The National Oceanic and Atmospheric Administration has predicted an above-average season this year because of record-warm ocean temperatures.

Associated Press reporters Patrick Whittle in Portland, Maine, and Haya Panjwani in Washington contributed. Collins contributed from Columbia, South Carolina.