A father who drove to help his wife with her overheated car which was pulled over on the side of a California motorway arrived to find his two children and mother-in-law had been killed in a car crash.

Four people died in the pile-up on Interstate 10 east of Los Angeles on Friday when a suspected drunk driver slammed into two vehicles that had pulled over, ABC news reported.

Prior to the crash, mother Maria Briseno had pulled her Honda over after it overheated, calling her husband to inform him of the problem. She and her 58-year-old mother stepped out of the car, leaving her 12-year-old son, Isaac Briseno, and her 12-year-old step-daughter, Ailyn Miguel, in the back of the vehicle.

A passer-by in a pick-up truck, who has since been identified as Jose Prieto, also pulled over and got out of his vehicle to help the family.

Shortly afterwards, a Nissan pick-up drove into the back of the Honda, killing the two children, their grandmother, and Mr Prieto. Ms Briseno survived and was taken to hospital with serious injuries.

Authorities are investigating if the driver of the Nissan vehicle was under the influence of alcohol at the time of the crash.

Family members have raised thousands of dollars through GoFundMe to help pay for funeral costs (GoFundMe)

Ms Briseno’s husband arrived at the scene moments after the police. California Highways Patrol officer Jesus Garcia said: “A lot of times we don’t have the family respond right away, but here, they were here within minutes of us arriving.

"And you have to deal with the emotions of them, seeing their family members who are dead at the scene.”

The driver survived the crash and is being held in hospital pending toxicology reports. He has refused to speak to police, Time reported.

Three fundraisers have been set up to support the families of those killed and help pay for funeral costs.

Ms Briseno’s brother, Giovany Rivera, set up a GoFundMe page “for the three good lives taken from us”. He said the day of the crash would “forever be scarred in my life” and that he hopes to give his family “the funeral they deserve”. The campaign, which has now closed, raised over $17,600 (£13,500) in two days.