Tim Parker, whose Brentwood home is near where the car crashed on Grand Boulevard, was jolted by the sound of the crash around 1 a.m. and went outside to see what happened.
The car was a ball of fire, he said.
"I heard a woman screaming, 'Help me, please help me,'" Parker said. He tried to use a garden hose from his home to douse the flames, but the fire was too strong.
The flames were so intense that police officers responding to a 911 call couldn't get near the burning vehicle, and by the time firefighters arrived and extinguished the flames, only the charred wreckage of the vehicle remained, authorities said.
Police say at least two people died in the inferno, but it may take time to identify them because the car was so badly damaged.
The cause of the crash is under investigation. Neighbors familiar with crash site on Grand Boulevard say speed have been a factor.
The road was closed for several hours while police investigated.