One person was killed early Friday morning in a multi-vehicle collision in Castaic.
It was reported at 2:51 a.m. on the northbound 5 Freeway just south of Templin Highway, said California Highway Patrol Officer Patrick Kimball.
One person died at the scene, Kimball said.
Local news from across Southern California
Six people were reported injured, at least three trapped and critical, according to Los Angeles County Fire Department Dispatch Supervisor Imy McBride.
Four vehicles, including a big rig, were involved in the crash, according to firefighters at the scene, McBride said.
It was believed the deceased was included in the initial report of six injured people, Kimball said.
The CHP issued a SigAlert shutting down lanes Nos. 1, 2, and 3 of the northbound 5 Freeway in the crash area.
The cause of the crash is under investigation.