A powerful tornado tore through a rural area of the Mississippi Delta on Friday night, causing injuries, widespread damage and downing power lines as severe weather that produced hail the size of golf balls moved through several southern states and prompted authorities to warn some in its path that they were in a "life-threatening situation."

The National Weather Service confirmed a tornado caused damage about 60 miles (96 kilometres) northeast of Jackson, Mississippi.

The rural towns of Silver City and Rolling Fork were reporting destruction as the tornado continued sweeping northeast at 70 mph (113 kph) without weakening, racing towards Alabama through towns including Winona and Amory into the night.

The National Weather Service issued an alert that didn't mince words: "To protect your life, TAKE COVER NOW!"

“You are in a life-threatening situation,” it warned. "Flying debris may be deadly to those caught without shelter. Mobile homes will be destroyed. Considerable damage to homes, businesses, and vehicles is likely and complete destruction is possible."

Cornel Knight told The Associated Press that he, his wife and their 3-year-old daughter were at a relative's home in Rolling Fork when the tornado struck. He said the sky was dark but “you could see the direction from every transformer that blew.”

He said it was “eerily quiet” as that happened. Knight said he watched from a doorway until the tornado was, he estimated, less than a mile away. Then he told everyone in the house to take cover in a hallway. He said the tornado struck another relative's home across a wide corn field from where he was. A wall in that home collapsed and trapped several people inside. As Knight spoke to AP by phone, he said he could see lights from emergency vehicles at the partially collapsed home.

Rolling Fork mayor Eldridge Walker told WLBT-TV he was unable to get out of his damaged home soon after the tornado hit because power lines were down.

He said emergency responders were trying to take injured people to hospitals. He did not immediately know how many people had been hurt.

A former mayor of Rolling Fork, Fred Miller, told the television station a tornado blew the windows out of the back of his house.

Storm chaser Reed Timmer posted on Twitter that Rolling Fork was in immediate need of emergency personnel and that he was heading with injured residents of the town to a Vicksburg hospital.

The Sharkey-Issaquena Community Hospital on the west side of Rolling Fork was damaged, WAPT reported.

The Sharkey County Sheriff's Office in Rolling Fork reported gas leaks and people trapped in piles of rubble, according to the Vicksburg News.

Some law enforcement units were unaccounted for in Sharkey, according to the the newspaper.

Rolling Fork and the surrounding area has wide expanses of cotton, corn and soybean fields and catfish farming ponds. More than a half-dozen shelters were opened in the state by emergency officials.

Mississippi Gov. Tate Reeves said in a Twitter post Friday night that search and rescue teams were active and that officials were sending more ambulances and emergency assets to those affected.

“Many in the MS Delta need your prayer and God's protection tonight,” the post said. “Watch weather reports and stay cautious through the night, Mississippi!”

Earlier Friday a car was swept away and two passengers drowned in southwestern Missouri during torrential rains that were part of a severe weather system.

Authorities said six young adults were in the vehicle that was swept away as the car tried to cross a bridge over a flooded creek in the town of Grovespring.

Four of the six made it out of the water. The body of Devon Holt, 20, of Grovespring, was found at 3.30 am, and the body of Alexander Roman-Ranelli, 19, of Springfield, was recovered about six hours later, Missouri State Highway Patrol Sgt. Thomas Young said.

The driver told authorities that the rain made it difficult to see that water from a creek had covered the bridge, Young said.

Meanwhile, the search continued in another southwestern Missouri county for a woman who was missing after flash flooding from a small river washed a car off the road. The Logan Rogersville Fire Protection District said there was no sign of the woman.

Two others who were in the car were rescued. Crews planned to use boats and have searchers walking along the riverbank.

When a woman's SUV got swept up in rushing flood waters Friday morning near Granby, Missouri, Layton Hoyer made his way through icy-cold waters to rescue her.

Some parts of southern Missouri saw nearly 3 inches (8 centimetres) of rain Thursday night and into Friday morning as severe weather hit other areas. A suspected tornado touched down early Friday in north Texas.

Matt Elliott, warning coordination meteorologist at the National Oceanic and Atmospheric Administration's Storm Prediction Center in Norman, Oklahoma, said the severe weather was expected across several states.

The Storm Prediction Center warned the greatest threat of tornadoes would come in portions of Arkansas, Louisiana, Mississippi and Tennessee. Storms with damaging winds and hail were forecast from eastern Texas and southeastern Oklahoma into parts of southeastern Missouri and southern Illinois.

More than 49,000 customers had lost power in Arkansas, Mississippi and Tennessee as of Friday night, according to poweroutage.us.

Louisiana Gov. John Bel Edwards warned of potential tornados reaching the state overnight and urged residents to prepare for severe weather, including damaging winds and hail. The risk of personal vulnerability increases with overnight severe weather as residents are less likely to receive warnings because they are asleep and tornadoes are more difficult to spot, according to the National Weather Service.

In Texas, a suspected tornado struck about 5 am in the southwest corner of Wise County, damaging homes and downing trees and power lines, said Cody Powell, the county's emergency management coordinator.

Powell said no injuries were reported.

The weather service had not confirmed a tornado, but damage to homes was also reported in neighbouring Parker County, said meteorologist Matt Stalley.