The gunman shot the victims at a house in Ridgecrest, east of Bakersfield, about 5 a.m. PDT and then warned he would "wreak havoc" in the community, Kern County Sheriff Donny Youngblood said.
The gunman called a Ridgecrest police officer's cellphone and said he would come to a police station and "kill all the officers but they had too many guns," the Los Angeles Times reported.
A county sheriff's deputy saw the man's car about 2 hours later and tried to pull it over but the man drove away with the deputy in pursuit. At one point, he started shooting at police and civilian traffic, using a shotgun and a handgun.
When he pulled over and popped the trunk lid, police saw a man and a woman in the trunk, which Youngblood said "changed the entire dynamic" of the chase. A short time later, police said, the man started shooting through the vehicle's rear seat into the trunk -- and sheriff's deputies, Ridgecrest police and California Highway Patrol officers opened fire, shooting and killing the gunman.
The two people in the trunk were hospitalized for treatment of gunshot wounds. It was not known when they had been shot, the sheriff's department said.
The names of the suspect and the victims were not reported, but Youngblood said Ridgecrest police "knew the suspect," the Times said.