Police say that no other factors besides the sudden dust storm have been identified as a cause of the 21 vehicle pileup in Montana over the weekend. 

The Friday, July 15th dust storm caused the pile-up along Interstate 90 near Hardin, Montana, killing six. Two of the victims have since been identified as children. No further details regarding the victims’ identities have been released, reported ABC 25 News.

“Everything is indicative of an isolated extreme weather event,” said Montana Highway Patrol Sgt. Jay Nelson. “What could people do? It really was just panic.”

Officials say the wind gusts that caused the dust storm reached speeds as high as 60 mph, causing zero visibility conditions for a mile-long stretch along I-90 during the evening commute and peak summer travel season. 

“We had a lot of debris and complete chaos,” Nelson continued, adding that it was the worst wreck he’s seen in his 24 years with the police force. 

“We will release more information as it becomes available and is appropriate out of respect of the lives lost and their loved ones,” said Gov. Greg Gianforte in a statement.