Authorities in Montana say that six people are confirmed dead in what officials are describing as "one of the most intense multi-vehicle accidents" in the state.
The Associated Press reported that the 21-car pileup happened Friday night on Interstate 90 near Hardin.
Montana Highway Patrol Sgt. Jay Nelson says the numbers of fatalities and injuries did not change overnight, and the accident scene has been totally cleared.
Officials said eight people were transported to nearby hospitals.
The AP reported that two children were among those who died in the crash.
Sgt. Nelson says information so far points to the conditions of the wind storm that caused the accident as an isolated, extreme weather event, and troopers do not believe there is any further danger to the public.
He says accident investigators are combing through all evidence and should have a thorough accident report on Monday when the coroner is expected to make a statement as well.
"In my 24 years of experience, this is one of the most intense multi-vehicle accidents we've had in the state of Montana," Sgt. Nelson said.
He says with the intense wind and dust it was a tragedy in an instant.
Eyewitnesses said the area was cloudy and dusty with low visibility shortly after the crash was reported around 4:30 p.m. Friday.
“It was like a snowstorm but dust. It was very low visibility, it was like fog. It reminded me of very dense fog," motorist Ariel Dehart told MTN News.
Sheyenne Scheeler, who snapped several photos of the scene, said she saw several cars that were crushed. She called the incident "gut-wrenching."
“The first thing that we saw was a pickup that had been pulling a camper, and the camper looked like it had been ripped open like a can. And then after that, we started seeing more cars that had rear-ended," Scheeler said.
On Twitter, Gov. Greg Gianforte issued a statement, saying he was deeply saddened to hear what happened.
I'm deeply saddened by the news of a mass casualty crash near Hardin. Please join me in prayer to lift up the victims and their loved ones. We're grateful to our first responders for their service.
— Governor Greg Gianforte (@GovGianforte) July 16, 2022