Los Angeles police officers responded to the 3300 block of Sabina Street around 10 p.m. Tuesday. Witnesses told police the woman was trying to get into the vehicle with the baby without a car seat.
The driver objected, and an altercation ensued. The woman was allegedly stabbed in the torso by the driver.
A good Samaritan became involved and was also injured.
The driver, whose name has not been released, was taken into custody.
Both victims suffered minor injuries, and the woman was transported to a local hospital for treatment.
It is unclear if the driver was injured, what company he drives for or what happened with the child after the altercation.
An investigation is ongoing.