Six pronounced dead, several more injured following huge pileup involving dozens of vehicles and many semi-trucks in foggy conditions on I-57 in Charleston, Missouri

The collisions began about 8 a.m. Thursday on Interstate 57 as thick fog enveloped the Charleston area, about 150 miles (241 kilometers) south of St. Louis.

Patients have been sent to at least three different hospitals in the area, and at least 12 ambulances and two air ambulances were called to the scene, the sheriff's office said. 

Photos from the scene show several tractor-trailers scattered along I-57, both on the road and in the median of the highway. The contents of the trucks -- some pink material, others white -- are also seen strewn on the road as crews surround the area.

The Mississippi County coroner confirmed a sixth death overnight, following the report Thursday of five deaths and many injuries in the pileups, Missouri State Highway Patrol Sgt. Jeff Kinder said.

Missouri State Highway Patrol Sgt. Jeff Kinder said about 50 vehicles were involved, including several semitrailer trucks. Officials said an approximately 25-mile stretch of the interstate will likely be closed well into Thursday night.

All lanes of I-57 between I-55 and the Illinois state line have been cleared and the highway has been reopened.