at least nine americans, including six children slaughtered in the mexican state of sonora. >> right on the road out of la mora >> reporter: the family, traveling in three vehicles was ambushed by gunmen believed to be local cartel, but it's unclear if the attack was targeted or a case of mistaken identity five were injured, several airlifted to arizona. witnesses describe a terrifying scene, a child shot in the back, babies trapped in a burning car among the dead, 30-year-old rhonita miller and her four children, including 8-month-old twins. 13-year-old devon langford survived the attack and then walked 14 miles to get help. >> it was awful seeing skulls just sitting there on the floor of the car burnt and broken. >> reporter: the victims are all american citizens living in northern mexico, descendants of mormon settlers that moved to the area decades ago. >> this is a whole new level of cartel violence.