The crash that reportedly involved a four-door sedan on westbound Highway 80 at the Cummings Skyway off-ramp in Crockett was reported around 2:20 a.m., according to the CHP.
The vehicle then caught fire, and it appears that one or more motorists stopped to help extinguish the blaze, according to the CHP.
One person involved in the crash was later pronounced dead.
The CHP issued a Sig-alert and closed all lanes of traffic at the scene of the crash at 2:41 a.m.
One lane of traffic around the scene of the collision remained closed just before 5 a.m.