Two people died and dozens were injured in a pileup involving 100 vehicles on a Louisiana interstate Monday, authorities said.

There were several “multiple-vehicle” crashes on Interstate 55, beginning at mile marker 22, in the northbound and southbound lanes, Louisiana State Police said in a statement.

Three 18-wheelers were involved in a crash, and at least two went up in flames, state police said.

St. John Parish Sheriff Mike Tregre said two people have died and about 30 people were injured.

In a Facebook post Monday morning about the crashes, state police cautioned drivers about fog.

“There is heavy fog in the area and drivers should avoid the area if possible and use alternate routes,” the post said.

Video of the aftermath of the pileup shows foggy conditions and at least one instance of pickup on top of another vehicle. Parts of Interstate 55 were closed and traffic was being diverted.

Eighteen people who were in the crash went to North Oaks Medical Center in Hammond, Louisiana. Of those people, three were in critical condition.