A mother and her eight-year-old son are among at least three people who died as a destructive storm system that stirred up tornadoes swept through the US.
To the north, it delivered blizzard-like conditions to the Great Plains and was expected to push more snow and ice into Appalachia and New England.
The wintery blast dumped more than two feet (60cm) of snow in parts of South Dakota.
To the south, it produced a number of tornadoes.
Outside New Orleans, eight people were taken to hospital and one woman was found dead after a suspected twister struck the community of Killona along the Mississippi River, damaging homes and flinging debris.
Sheriff Greg Champagne said: “There was debris everywhere. This was a horrific and a very violent tornado.”
And about 280 miles (450 kilometres) away in northern Louisiana, emergency services found the bodies of a mother and eight-year-old boy reported missing after another tornado swept away their mobile home.
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A steady stream of tornado warnings was issued on Wednesday across large portions of Louisiana, Mississippi and Alabama.
One, which touched down in southwest Louisiana, damaged several buildings on the campus of a hospital, another, in neighbouring Mississippi, destroyed four large chicken houses – one containing 5,000 roosters.
Mobile homes at a nearby park were reduced to piles of shredded debris.
Dozens of homes and businesses were destroyed in Texas, too.
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At least five people were injured In the Dallas suburb of Grapevine, police said. A possible tornado blew the roof off the city’s municipal service centre, leaving debris dangling from power lines.
The forecast was for more severe storms with additional tornadoes to be expected across an area of the Gulf Coast region populated by nearly three million people from New Orleans to Mobile, Alabama.
More damaging weather was also forecast for the Florida panhandle.
Icy weather from the huge storm was expected to affect the US from coast to coast at some point, with ice and snow heading to the eastern US in coming days.
Frank Pereira, a meteorologist with the National Weather Service in College Park, Maryland, said: “This system is notable for the fact that it’s going to impact areas all the way from California to eventually the northeast.”