A head-on collision killed two drivers around 9 a.m. Wednesday on Pleasant Valley Road between Oxnard and Camarillo.
Police said they did not have passengers in their cars.
Witnesses said the collision caused a fire.
Relatives of both drivers grieved on the side of the road as California Highway Patrol officers investigated.
Officer Steve Reid said a woman driving a GMC pickup truck northbound lost control and veered into the path of a Ford Mustang driven by a man.
A passerby tried to put the fire out with an extinguisher, but it kept burning until firefighters arrived.
The medical examiner said it may take awhile to release the names of the drivers killed.
The CHP is asking anyone who witnessed of crash to contact Officer Micah Weilbacher or Officer Kevin Orr at 805-477-4100.