UPDATE: Authorities say 2,000 people evacuated in the North Carolina mountains because of worries a dam might break can return to their homes.

McDowell County Emergency Management sent a message to the public around 10:15 a.m. Wednesday saying engineers have determined the dam at Lake Tahoma is safe.

Heavy rains from the fringes of Subtropical Storm Alberto caused widespread flooding Tuesday evening. Emergency officials order the evacuations because an engineer inspecting the dam was worried it might break before officials could get a better look in the daylight.

The dam is about 80 miles (129 kilometers) northwest of Charlotte.

Dozens of roads in western North Carolina were blocked by mudslides or flooding, including Interstate 40 which closed for several hours near Old Fort.

Forecasters warn storms could bring more flooding Wednesday, but say the heavy rains will be isolated and not widespread.

PREVIOUS STORY: Thousands of people were being evacuated early Wednesday after a landslide caused by heavy rains raised fears about the integrity of a dam in North Carolina, officials said.

Residents living below Lake Tahoma were ordered to leave after the dam was inspected by an engineer.

The National Weather Service said a flash flood emergency was in place for McDowell County including the city of Marion, which is home to around 7,800 people, and Old Fort, which has a population of 900. Authorities urged residents to seek higher ground immediately.

Lake Tahoma is about 5 miles northwest of Marion. Marion is about 36 miles east of Asheville.

The flash flood emergency was scheduled to remain in place until 10:30 a.m. ET.

As of 4:15 a.m. ET, officials in McDowell County continued to report "widespread flooding due to heavy rainfall of 4-6 inches over the past 24 hours," the NWS said. "This is causing significant and life-threatening flooding countywide."

It added: "Floodwaters have reached levels not seen since the September 2004 floods associated with Hurricanes Frances and Ivan. Numerous evacuations of residences, businesses, and campgrounds, road closures, water rescues, and landslides are ongoing."

McDowell County officials said at 6:11 a.m. ET that the risk of imminent failure remained at Lake Tahoma Dam and that the evacuations would continue until engineers could thoroughly inspect the dam during daylight hours.

William Kehler, McDowell County Emergency Services director, told NBC News that "several thousand" people lived in the mandatory evacuation zone. As of 3:20 a.m. ET, no injuries or fatalities had been reported.

 The rain is part of the soggy remnants of Alberto, the first named storm of the Atlantic hurricane season.

Flash flood watches were in effect early Wednesday for parts of several states from Alabama through Tennessee, Kentucky, Illinois, the Carolinas and Virginia and West Virginia.

A television news anchor and a photojournalist died Monday while covering the weather, when a tree became uprooted from rain-soaked ground and toppled onto their SUV in North Carolina.

NBC affiliate WYFF of Greenville, South Carolina, said news anchor Mike McCormick and photojournalist Aaron Smeltzer were killed.