The New Mexico teenager accused of fatally shooting his parents and three younger siblings told authorities he was annoyed with his mother and had been having homicidal and suicidal thoughts, according to a probable cause statement.
Nehemiah Griego, 15, remained in custody Monday on charges of murder and child abuse resulting in death. He was arrested following the shootings Saturday at a home in a rural area southwest of Albuquerque where he lived with his family.
A Bernalillo County sheriff's detective questioned the teen Saturday night and the details of their conversation were spelled out in the statement.
The teen allegedly told the detective that he took a .22 caliber rifle from his parents' closet around midnight Saturday and shot his mother in the head while his younger brother slept next to her.
Griego told the detective that his brother did not believe him that their mother was dead so he showed his mother's bloody face to his brother and then shot him, according to the statement.
He's accused of then shooting his two young sisters in their room. He retrieved an AR-15 rifle from his parents' closet and waited in a downstairs bathroom for his father to come home. The statement said he shot his father multiple times after he passed the bathroom doorway.
The teen said he reloaded the guns so "he could drive to a populated area to murder more people," according to the statement.
His plan, the statement said, was to "shoot people at random and eventually be killed while exchanging gunfire with law enforcement."
Sheriff's spokesman Deputy Aaron Williamson said Monday he couldn't immediately comment on the document.
Detectives have spent two days collecting evidence and trying to piece together what led to the violence.
"There's no other way to say it, except that we have a horrific crime scene down there that we are working on," Bernalillo County Sheriff Dan Houston said Sunday.
The detectives had finished their work at the home by Monday afternoon. The metal gate at the home's entrance was shut, a small bouquet of purple flowers was on the top of the gate and at each side there were religious signs, including one that read "Jesus is the reason for the season."