Twenty-nine vehicles are involved in a crash on Oklahoma City Boulevard, firefighters said.
The crash happened Monday morning in between Pennsylvania Avenue and Agnew as freezing temperatures and freezing drizzle helped make roadways slick in the state.
Five people were taken to local hospitals and one was taken in critical condition, Oklahoma City fire Battalion Chief Benny Fulkerson said.
Firefighters said vehicles were stacked next to each other.
Some other people involved in the crash went to hospitals on their own to be checked out, Fulkerson said.