The CHP tells FOX40 they were initially told by a witness that a Hyundai Sonata was stopped on the freeway with its lights off when a truck towing another car plowed into it. However investigators say they are reviewing other evidence that conflicts with that report.
The CHP says a Toyota Sienna then crashed into the left side of the tow truck and all three cars came to a stop.
The driver of a Dodge Ram pickup put his flashers on as he pulled over to render aid to the crash victims and help arriving officers, according to the CHP. Two cars, a Dodge Caravan and a Chevy Camaro, slammed into the back of his truck, and the Camaro burst into flames.
The driver of the Hyundai, 62-year-old Bennie Harriel, and her grandson, Tayarrie Hatchett-Sims, were killed. According to Tayarrie's mother, he turned 15 on Friday.
Two people, Tayarrie's friend, who was the third passenger in Harriel's car, and the driver of the Dodge Caravan, are in critical condition. The friend is in the intensive care unit, according to Tayarrie's mother.
The driver who hit the tow truck sustained moderate injuries.
CHP North Sacramento is investigating and does not know if alcohol or drugs were a factor in the crashes.
Stay with FOX40 for more updates.