The newspaper reports that it all started when the suspect went to a trucking business around 5:30 p.m. with his wife to confront another man.
"We have six deceased, one is the suspect and five are victims", said Lieutenant Mark King of the Kern County sheriff's office after the shooting in the city of Bakersfield.
The attacker then fatally shot two more men at another location, before hijacking a vehicle with a woman and a child on board.
There was no immediate word on what sparked the shootings that took place at a home and a business in Bakersfield, southern California, which is some 145 kilometres north of Los Angeles. The area of the shooting spree was in unincorporated Bakersfield, which is patrolled by the sheriff's department.
Youngblood told reporters that 10 to 15 minutes elapsed from the first shooting until the gunman killed himself, KBAK-TV reports.
Police say there are at least 30 witnesses, KRON reported.
"Six people lost their lives in a very short period of time". Obviously, there was a kind of situation that caused the husband to be extremely upset.
He then hijacked a nearby vehicle with a mother and child inside, and headed toward the highway. There is no information yet if the other four were related to the attacker. He said the officer who confronted the suspect wore a body camera, but the footage has not been released.
As the gunman was driving away he was spotted by a deputy and suddenly pulled into a parking lot, where he shot himself in the chest and died. The suspect went with his wife together to the business to confront the man, he added.