US rescuers desperately searched for survivors on Sunday after tornadoes killed at least 94 and left towns in ruin, with emergency crews racing against time to find dozens still missing from a collapsed Kentucky factory.

Iran PressAmerica: The wave of twisters, including one that traveled more than 320 kilometers, was reportedly one of the largest storm outbreaks in American history.

With the death toll all but certain to rise, dozens of search and rescue officers were helping stunned citizens across the US heartland sift through the rubble of their homes and businesses overnight.

Kentucky Governor Andy Beshear said on Sunday raised the state’s death toll by 10, to more than 80, and said he expected the tally to rise. “That number is going to exceed more than 100,” Beshear told CNN.

The tornadoes tore through the US Midwest and South on Friday night leaving a trail of death and destruction in its path stretching hundreds of miles.

In the town of Dawson Springs alone, with a population of about 2,700, the list of missing people spanned eight pages, Beshear said. “The massive, widespread damage makes rescue efforts challenging.”

But nowhere suffered as much as the small town of Mayfield, Kentucky, where the powerful twisters, which weather forecasters say are unusual in winter, destroyed a candle factory – killing many – as well the fire and police stations.

Across the town of 10,000 people in the state’s southwestern corner, homes were flattened or missing roofs, giant trees had been uprooted and street signs were mangled.

The genesis of the tornado outbreak was a series of overnight thunderstorms, including a supercell storm that formed in northeast Arkansas. That storm moved from Arkansas and Missouri and into Tennessee and Kentucky.

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