Dense fog triggers deadly crash involving dozens of vehicles in Missouri

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Dense fog causes major crash on I-57 in Missouri, resulting in multiple fatalities

Dense fog caused a major crash on I-57 in Missouri Thursday morning, resulting in multiple fatalities and injuries. (Video: KFVS-TV)

CHARLESTON, Mo. -- At least 5 people were killed and multiple others injured in a weather-related crash involving dozens of semi-trucks and vehicles Thursday morning in Missouri.

Officials say a dense fog patch descended on Interstate 57 near Charleston, dropping visibility to less than 100 feet.

"Conditions were extremely foggy," Zach Bolden, the director of Mississippi County EMS, told KFVS-TV. "We believe someone hit their brakes and someone else ran into the back of them, triggering a chain reaction."

Up to 25-50 vehicles were involved in the crash, many of them semi-trucks. Some of the trucks caught fire in the aftermath.

The Mississippi County coroner told KFSV-TV five people had died. The number of injured has not been released, but medics found plenty of "walking wounded" when they arrived on the scene.  Some have been rushed by ambulances to nearby hospitals while at least one person was flown by medical helicopter.

Crews say it will take "several" hours to clean up the crash site.

In the meantime, officials say to take it slow if you find yourself inside a dense fog bank.

"Drive slow and cautiously, turn headlights on, your flashers on, or pull over," Bolden said.