US President Joe Biden has pledged support to states affected by a swarm of devastating tornadoes that demolished homes, levelled businesses and left at least 100 people feared dead.
Describing the tornadoes as likely "one of the largest" storm outbreaks in history, Biden on Saturday approved an emergency disaster declaration for the worst-hit state of Kentucky, where at least 22 people have been confirmed dead.
"It's a tragedy," said a shaken Biden. "And we still don't know how many lives are lost and the full extent of the damage."
He added, "I promise you, whatever is needed – whatever is needed – the federal government is going to find a way to provide it."
The powerful twisters, which weather forecasters say are unusual in cooler months, destroyed a candle factory in Mayfield, Kentucky, ripped through a nursing home in neighbouring Arkansas, and killed at least six workers at an Amazon warehouse in Illinois.
Kentucky Governor Andy Beshear said the collection of tornadoes was the most destructive in the state's history. He said about 40 workers had been rescued at the candle factory, which had about 110 people inside when it was reduced to a pile of rubble.
[...] Mayfield Fire Chief Jeremy Creason, whose own station was destroyed, said the candle factory was diminished to a "pile of bent metal and steel and machinery" and that responders had to at times "crawl over casualties to get to live victims".
[...] The tornado outbreak was triggered by 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.
Unusually high temperatures and humidity created the environment for such an extreme weather event at this time of year, said Victor Gensini, a professor in geographic and atmospheric sciences at Northern Illinois University.
"This is an historic, if not generational event," Gensini said.
If early reports are confirmed, the twister may have touched down for nearly 250 miles (400km), he said, a path length longer than the longest tornado on record, which tracked for about 220 miles (355 km) through Missouri, Illinois and Indiana in March 1925.
[...] The National Weather Service's Storm Prediction Center said it received 36 reports of tornadoes touching down in Illinois, Kentucky, Tennessee, Missouri, Arkansas, and Mississippi.
[...] In Edwardsville, Illinois, Fire Chief James Whiteford said at least six people were killed when an Amazon warehouse collapsed. Some 45 people survived.
[...] In Monette, Arkansas, one person was killed and five seriously injured when a tornado tore through a nursing home with 90 beds.