DIVERNON, Illinois (AP) — A windstorm in central Illinois kicked up dangerous clouds of blinding dust off farm fields Monday, causing numerous crashes that killed at least six people on Interstate 55, police said.

The late morning crashes involved 40 to 60 cars and multiple tractor-trailers, two of which caught fire, Illinois State Police Major Ryan Starrick said.

He said at least six people died, all in the northbound lanes, and more than 30 people on both sides of I-55 were transported to hospitals with injuries.

“The only thing you could hear after we got hit was crash after crash after crash behind us,” said Tom Thomas, 43, who was traveling south to St Louis.

I-55 was shut down in both directions in Montgomery County, 75 miles (120 kilometers) north of St Louis, and likely won’t reopen until Tuesday.

Starrick told reporters that it was a spring version of a “whiteout situation” typically seen in winter snowstorms. Governor J.B. Pritzker described the scene as “horrific.”

“The cause of the crashes is due to excessive winds blowing dirt from farm fields across the highway, leading to zero visibility,” Starrick said.

Dairon Socarras Quintero, 32, who was driving to St Louis to make deliveries for his custom frame company based in Elk Grove Village, said that after his truck hit the vehicle in front of him, he exited and moved to the side of the road to ensure his safety, then returned after the chain reaction of crashes ended behind him.

Socarras Quintero said the dust continued to blow ferociously as he checked on other motorists and emergency personnel arrived. He held up his backpack, which was caked with dust even though it was inside a closed truck cab.

Winds at the time were gusting between 35 mph (56 kph) and 45 mph (74 kph), 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.”

Evan Anderson, 25, who was returning home to St Louis from Chicago, said a semi turned before striking his vehicle, sparing him from even more damage.

“You couldn’t even see,” Anderson said. “People tried to slow down and other people didn’t, and I just got plowed into. There were just so many cars and semitrucks with so much momentum behind them.”

Kevin Schott, director of emergency services in Montgomery County, said it was a “very difficult scene” and one that’s “very hard to train for.”

“We had to search every vehicle, whether they were involved in the accident or just pulled over, to check for injuries,” he said, adding that people were “upset — visibly so, understandably so.”

Authorities set up staging areas away from the crash site to help travelers reunite with friends and family.