A three-car accident shut down part of Interstate 29 early Thursday.
According to the Missouri State Highway Patrol, 12 people were sent to Heartland Regional Medical Center.
Authorities were called to the 40-mile marker of the I-29 southbound lanes a little after midnight.
City, county and Missouri Troop H authorities responded to the accident.
Multiple ambulances from Heartland, Northland Regional Ambulance Service and Platte City were needed to take the injured to Heartland.
Traffic ground to a halt as both southbound lanes of traffic were blocked for at least an hour.
One of the drivers in the accident, Tari Hovey, was taken to Heartland Regional Medical Center with serious injuries.
The chain accident occurred when Ms. Hovey’s vehicle struck the rear of a van driven by Lal T. Hup, of Kansas City, Kan., which then hit a tractor-trailer driven by Thomas W. Crawford, of Kansas City, Kan.