ERICK, Okla. - At least two people have been killed and 12 others injured in a fiery, 16-vehicle pileup on Interstate 40 near Oklahoma's western border with Texas.

Oklahoma Highway Patrol Trooper Betsy Randolph says she was notified of the accident about 8:30 a.m. Saturday. Interstate 40 remained closed in both directions near Erick late Saturday.

Randolph says investigators aren't sure what caused the accident involving semi-trucks and smaller vehicles. The National Weather Service issued a dense fog advisory for the area, but Randolph said she didn't know if that was a factor.

Randolph says emergency responders were checking to see if anyone was trapped in the vehicles, some of which caught fire.

Oklahoma Department of Transportation spokesman Cody Boyd says traffic was diverted off the highway onto service roads.