A windstorm in Illinois kicked up dangerous clouds of blinding dust off farm fields, causing numerous crashes and killing at least six people on Interstate 55, police said.
The late morning crashes involved 40 to 60 cars and multiple lorries – two of which caught fire, Illinois State Police Major Ryan Starrick said.
At least six people died, he said.
I-55 was shut down in both directions in Montgomery County, 75 miles north of St Louis.
Mr Starrick told reporters that it was a spring version of a “whiteout situation” typically seen in winter snowstorms.
“The cause of the crashes is due to excessive winds blowing dirt from farm fields across the highway, leading to zero visibility,” he said.
Winds at the time were gusting between 35mph and 45mph, the National Weather Service said.
“It’s very flat, very few trees,” meteorologist Chuck Schaffer said.
“It’s been very dry across this area really for the last three weeks. The farmers are out there tilling their fields and planting. The top layer of soil is quite loose.”
Mr Starrick said more than 30 people were transported to hospitals with injuries following the crashes, which occurred on both the southbound and northbound lanes.
He said the I-55 would be closed until late morning or early afternoon on Tuesday.
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