The crash happened in the area of Avenue 368 and Road 52 around 3:30 pm on Saturday afternoon.
Authorities say a driver in a Camry was under the influence of alcohol when he suddenly veered across the center line into oncoming traffic.
He struck a minivan carrying two men and a woman head-on.
The men in the minivan were killed and the woman has been rushed to hospital with significant injuries.
After this initial crash, the Camry also struck a Chevy Tahoe with a family of five. They are expected to be ok.
The man driving the Camry was also killed in the crash. California Highway Patrol officers say they believe he was intoxicated. They say they found beer cans and a strong odor of alcohol in the car.
According to witnesses, the driver in the Camry was speeding above the 55 mph limit.
CHP officers are working to determine what led up to the crash and identifying the three people who died.
This story is developing and will be updated.