Sept. 27 (UPI) — Dozens of people have died and millions are without power in the southeastern United States as a result of Helene, a tropical storm that struck Friday morning after making landfall in Florida overnight as a powerful Category 4 hurricane.

At least 15 people have died in Georgia in Helene-related incidents, the governor’s spokesman Brian Kemp told reporters in an afternoon update, hours after the governor earlier confirmed that 11 residents had been killed by high winds and flooding.

Meanwhile, Columbia, South Carolina, has reported at least 13 deaths, according to WYFF-TV. Two of the victims were firefighters who died in Saluda County when their vehicle was struck by a tree, Gov. Henry McMaster confirmed at an afternoon news conference.

At least seven people have died in Florida, including five in Pinellas County, including the city of Tampa, according to Sheriff Bob Gualtieri, who described the damage to the county’s beaches as a “war zone.”

Additional fatalities were reported in North Carolina, where the National Weather Service described Helene as one of the most significant weather events of the modern era in the region. Raleigh, North Carolina reported fatalities in Charlotte and Catawba counties, according to WRAL-TV

PowerOutage.us reported that as of Friday afternoon, 1.2 million homes were without power in South Carolina, 915,000 in Georgia and 700,000 in Florida. As of 4 p.m. Friday, the center of the storm was 50 miles southeast of Louisville.

As Friday progressed, tornadoes continued to threaten areas across the Southeast. The National Weather Service confirmed two twisters in North Carolina, including one near Garland, North Carolina, and another in Nash County near Rocky Mount, North Carolina.

Officials said 15 people were injured by the Rocky Mount tornado, four of them seriously, and 11 buildings were damaged.

City officials imposed a curfew in Asheville, North Carolina “to ensure public safety” as most of the city of 94,000 remained without power.

In East Tennessee, more than 50 people were stranded on the roof of Unicoi County Hospital in Erwin, according to Sen. Bill Hagerty, R-Tenn., who called it a “tragic situation.” He later reported that “everyone was safely rescued” from the roof, but warned that “more trouble is on the horizon for East Tennessee communities.”

Virginia State Police said they helped rescue 58 patients trapped on a roof.

More than 800 flights were canceled on Friday, affecting many parts of the country because Atlanta’s Hartfield-Jackson International Airport, one of the airports affected by the storm, is one of the country’s main transportation hubs.

Other major airports affected were Charlotte Douglas International Airport in North Carolina and Tampa International Airport in Florida.

“The primary threat is very heavy rainfall across parts of the southeastern United States, causing historic and life-threatening flooding,” the National Hurricane Center said Friday. “Helene is expected to move more slowly toward the northwest later (Friday) and then stall over the Tennessee Valley (Friday evening) and through the weekend as it connects with the mid-to-upper low.

“This merger will also lead to the extratropical transformation, which is expected to occur later (Friday). The expected slowdown could cause significant flooding in the Ohio and Tennessee valleys in the southern Appalachians over the weekend.”