A 25-year-old St. Louis woman is accused of killing her two small children Yokela Smith, 4, and Levada Brown, 5.

Relatives of the woman, Yokeia Smith, say a third child, 8 years old, may have seen his mother kill his 5-year-old sister and 4-year-old brother.

Autopsies on Thursday determined the two children were both shot once in the head at close range with a shotgun and died instantly.

Yokeia Smith, who has not been formally charged, allegedly then got into her car before running over a father and son. The woman was arrested outside the KMOV news station in downtown St. Louis waving around a large shotgun after stepping out of her car on the side of a main road.