A man who shot and killed 10 people, including his mother, in southeast Alabama wrote a letter of explanation before he did so.
Michael McLendon, 28, killed his mother, grandmother, uncle, two cousins and five others, including an 18-month-old girl, on Tuesday.
Investigators have found a list of people he bore grudges against. They said on Thursday that he was motivated at least in part by revenge against perceived slights and injustices.
McLendon, who lived with his mother in Kinston, killed her first some time before setting out on the rampage. He also set the house on fire and shot the family dogs.
Aside from family members, McLendon killed the wife of a local deputy sheriff and her 18-month-old daughter, who were visiting one of McLendon's relatives.
Three people, including a motorist at a gas station, were killed at random as McLendon drove through the town of Samson.
He was armed with two military assault rifles, a handgun and a shotgun. More than 125 rounds were fired in the rampage.