A 65-year-old father was killed early on Monday on northbound Interstate 15 near San Diego while going to help his daughter, whose car had stalled, according to the California Highway Patrol (CHP) account reported by NBC 7 San Diego and other local coverage.

CHP said the daughter was driving a Mazda that stopped in the centre divider, possibly because of a mechanical fault or a flat tyre, with her children in the vehicle. She called her father for help. He was struck by a grey Toyota Corolla driven by a 30-year-old man from Los Angeles as he crossed lanes toward the median, CHP Sergeant Ray Scheindes was cited as saying, adding that how the father arrived at the scene before the impact remains unclear.

The first collision set off a chain: a Toyota Highlander then struck the Corolla and a silver Nissan Versa sideswiped another vehicle, according to the reports. The drivers of the Corolla and the Highlander were taken to a local hospital; their conditions were not immediately disclosed. The daughter and her children were not physically injured.

CHP diverted northbound traffic to State Route 52 while investigators and cleanup crews worked, and all northbound lanes stayed closed for several hours before reopening at about 8:45 a.m., NBC 7 reported. The investigation is ongoing. The man's name was not released in the reports cited here. This is a death/tragedy story, so no incident scene is depicted in the illustration.