A ray of hope has emerged from the aftermath of a barrage of tornadoes that obliterated a Kentucky town and killed people in five states.

Late on Sunday (local time), representatives of a candle factory flattened in the disaster said far fewer people might have died than previously feared.

Officials had said the death toll could soar past 100 from twisters that tore through at least six states in the US Midwest and South on Friday night, while seeing little chance of finding survivors in the rubble two days later.

In Kentucky, Governor Andy Beshear estimated the death toll at 80 and said it was certain to rise above 100. But that was based on the suspicion scores were killed when a candle factory was destroyed in the small city of Mayfield.

Up to 70 people at the factory had been feared dead. But that number could be revised down to 16 or fewer, a company spokesman said, raising the possibility the governor’s death toll estimate could come down significantly.

Among the 110 people who were at the factory, eight have been confirmed dead and eight others remained missing, said Bob Ferguson, a spokesman for Mayfield Consumer Products.

“There were some early reports that as many as 70 could be dead in the factory. One is too many, but we thank God that the number is turning out to be far, far fewer,” Mr Ferguson told Reuters, adding rescue teams were still searching for the eight who remained unaccounted for.

It was unclear how many factory workers Mr Beshear was counting in his estimated death toll, which he formulated on Saturday and said on Sunday remained unchanged.

“We’re still getting information in on the candle factory. The owner has been in contact and believes he has some different information,” he said on Sunday night (local time).

“We are trying verify it. If so, it may be a better situation and the miracle we were hoping for.”

While Kentucky was hardest hit, six workers were killed at an Amazon warehouse in Illinois after the plant buckled under the force of the tornado.

A nursing home was struck in Arkansas, causing one of that state’s two deaths. Four were reported dead in Tennessee and two in Missouri.

Nowhere suffered as much as Mayfield, a community of about 10,000 in the southwestern corner of Kentucky, where the large twisters also destroyed the fire and police stations.

“It didn’t take a roof, which is what we’ve seen in the past. It exploded the whole house. People, animals … just gone,” Mr Beshear said of the storm system, which he described as the worst in the state’s history.

More than 300 members of the National Guard were going door to door and removing debris. Teams were working to distribute water and generators.

The US Federal Emergency Management Agency was opening shelters and sending teams and supplies, including 30,000 meals and 45,000 litres of water.

Mayfield resident Laurie Lopez, 53, said the tornado “sounded like a freight train going through a brick house”.

-AAP