A speeding SUV hit four pedestrians on a small crowded road in the southern province of Binh Duong on Thursday, killing one woman.
Nguyen Thi An, 28, died on the spot. The other casualties were a local woman, a South Korean man and a three-year-old boy.
An online video shows the man lying unconscious on the ground at around 6 p.m. All the victims were rushed to hospital.
The car only stopped after hitting a truck parked on the road.
Angry locals grabbed the driver, Le Van Son, 48, and handed him over to police.
The investigation is ongoing.