KENTUCKY, United States (AP) — Torrential rains unleashed devastating floods in Appalachia, Kentucky, on Thursday, as fast-rising water killed at least three people and sent people scurrying to rooftops to be rescued.

Water gushed from hillsides and flooded out of streambeds, inundating homes, businesses and roads throughout eastern Kentucky. Parts of western Virginia and southern West Virginia also saw flooding. Rescue crews used helicopters and boats to pick up people trapped by floodwaters.

“In a word, this event is devastating,” Kentucky Governor Andy Beshear said as he announced the deaths and warned that more lives would surely be lost. “And I do believe it will end up being one of the most significant, deadly floods that we have had in Kentucky in at least a very long time.”

In Breathitt County in Kentucky, Krystal Holbrook’s family raced against surging floodwaters in the early morning hours to move possessions to higher ground. Their ordeal began around 4:00 am Thursday as they scurried in the dark to move vehicles, campers, trailers and farm equipment. But as the water kept rising throughout the day, the concern was that “higher ground is getting a little bit difficult”, she said.

“It looks like a huge lake back here,” she said.

Beshear warned that property damage in Kentucky would be widespread. The governor said officials were setting up a site for donations that would go to residents affected by the flooding.

“There are going to be a lot of people out there that need our help,” he said. “There’s going to be a lot of people that are going to be displaced. And this is yet another disaster that is going to take some time to rebuild.”

Beshear was referring to the ongoing rebuilding effort in western Kentucky, where several towns were devastated by deadly tornadoes late last year.

Dangerous conditions and continued rainfall hampered rescue efforts Thursday, the governor said.

“We’ve got a lot of people that need help that we can’t get to at the moment,” Beshear said. “We will.”

Flash flooding and mudslides were reported across the mountainous region of eastern Kentucky, western Virginia and southern West Virginia, where thunderstorms dumped several inches of rain over the past few days.

In Kentucky’s Perry County, Marlene Abner Stokely posted a video on Facebook showing how Squabble Creek overflowed and swamped a historic church.

“Guys, I don’t know how much more rain Buckhorn can handle,” she wrote. “You can see it is pretty much taken over.”

With more rain expected in the area, the National Weather Service said additional flooding was possible into Friday in much of West Virginia, eastern Kentucky and south-west Virginia. Forecasters said the highest threat of flash flooding was expected to shift farther east into West Virginia.

Poweroutage.us reported more than 31,000 customers without electricity in eastern Kentucky, West Virginia and Virginia, with the bulk of the outages in Kentucky.

“There are a lot of people in eastern Kentucky on top of roofs waiting to be rescued,” Beshear said earlier Thursday. “There are a number of people that are unaccounted for, and I’m nearly certain this is a situation where we are going to lose some of them.”

Rescue crews worked throughout the night helping people stranded by the rising waters in eastern Kentucky’s Perry County, where Emergency Management Director Jerry Stacy called it a “catastrophic event”.

“We’re just in the rescue mode right now,” Stacy said, speaking with The Associated Press by phone as he struggled to reach his office in Hazard. “Extreme flash flooding and mudslides are just everywhere.”

The storms hit an Appalachian mountain region where communities and homes are perched on steep hillsides or set deep in the hollows between them, where creeks and streams can rise in a hurry. But this one is far worse than a typical flood, said Stacy, 54.

“I’ve lived here in Perry County all my life and this is by the far the worst event I’ve ever seen,” he said.

Roads in many areas weren’t passable after as much as six inches (15 centimetres) of rain had fallen in some areas by Thursday, and 1-3 more inches (7.5 centimetres) could fall, the National Weather Service said.

Beshear said he has deployed National Guard soldiers to the hardest-hit areas, and three parks in the region were opened as shelters for displaced people.

Breathitt County’s courthouse was opened overnight in Kentucky, and Emergency Management Director Chris Friley said the Old Montessori School would provide more permanent shelter once crews can staff it.

Perry County dispatchers told WKYT-TV that floodwaters washed out roads and bridges and knocked homes off foundations. The city of Hazard said rescue crews were out all night, urging people on Facebook to stay off roads and “pray for a break in the rain”.

In West Virginia’s Greenbrier County, firefighters pulled people from flooded homes and five campers who got stranded by high water in Nicholas County were rescued by the Keslers Cross Lanes Volunteer Fire Department, WCHS-TV reported.

Governor Jim Justice declared a state of emergency for Fayette, Greenbrier, Logan, McDowell, Mingo, and Wyoming counties in West Virginia, after severe thunderstorms packing heavy rains and high winds this week caused significant local flooding, downed trees, power outages and blocked roads.

Communities in south-west Virginia also were flooding, and the National Weather Service office in Blacksburg, Virginia, warned of more showers and storms on Thursday.

In Buchanan County, which was hit by severe flooding two weeks ago, preliminary assessments of the previous flooding were postponed for safety as new water poured in, according to Virginia Department of Emergency Management spokesperson Lauren Opett. Officials were determining whether it’s feasible to conduct the assessments virtually, she said.

And in Wise County, the Office of Emergency Management warned of imminent flooding and road closures in the Pound Bottom area on Thursday morning. Officials advised residents to shelter in place until floodwaters recede, or evacuate to a shelter in an elementary school.