STOCKTON, Calif. (AP) — A woman whose toddler was killed when a California sheriff’s deputy rear-ended her car has died of her injuries, authorities said Thursday.

Kalesha Johnson, 23, died Wednesday at a hospital, the Los Angeles Times reported. Johnson’s 1-year-old son, who was in the backseat, died at a hospital hours after the Saturday night collision on Interstate 5 near Stockton.

The California Highway Patrol said in a statement that a marked San Joaquin County Sheriff’s Office patrol car rear-ended the woman's sedan, sending it down an embankment, the Stockton Record reported.

The crash is under investigation. The CHP said alcohol or drugs are not believed to be a factor.

Home surveillance video acquired by ABC10 shows the woman's car coming to a stop before it is struck from behind by the patrol vehicle and pushed off the highway. It's unclear why the car came to a stop.

The deputy took the boy out of the mangled car and began CPR. People described as “good Samaritans” by the CHP also rushed to the scene, extricated the mother and began CPR.

The deputy, who has not been identified, was treated at a hospital and released.