ALBUQUERQUE, N.M. (AP) — The New Mexico teen accused of killing his family and plotting to randomly gun down Wal-Mart shoppers spent much of the day after the early morning slayings at his church, wandering the campus as dozens of Sunday school teachers were being trained on how to deal with a shooter, a security official said.
But it wasn't until hours later, former police officer and Calvary Albuquerque security chief Vince Harrison said, that he knew something had gone terribly wrong.
Harrison, who led the safety training Saturday morning, said he was called back to the church that evening after 15-year-old Nehemiah Griego told a pastor he found his family dead in their home.
"When I met Nehemiah, I knew something wasn't right," Harrison said Wednesday. "I could feel it, I could see it in his eyes and I could see it in his behavior and his demeanor so the red flags went up and that's when I called the sheriff's department."
Harrison, who had known the Griego family for about 10 years, said he drove the teen back to the family's rural southwest Albuquerque home to meet authorities, interviewing him along the way.
"He went into detail of where they were, where the guns were and he was very matter-of-fact, really cold so I knew something wasn't right," Harrison said.
After finding the bodies, sheriff's officials say, they took the teen to headquarters. During questioning, they say he confessed to shooting his mother and three younger siblings in their beds shortly after 1 a.m., then waiting in a bathroom with a military-style semi-automatic rifle to ambush his father upon his return from an overnight shift at a homeless shelter.
They say he also told them he had reloaded the family's rifles and taken them with him in the family van with plans to randomly shoot more people.
"That sends chills down my spine," Harrison said. "But obviously God had a different plan."
Harrison said several people spotted Griego at the church throughout the day and told him hello, thinking nothing of it until his arrest. He said officials then reviewed security video and found the teen had spent much of the day there.
The video has been turned over to investigators, who have been working to piece together what led to the violence and what happened in the hours that followed.
Harrison said he doesn't know why Griego decided to come to the church, but that it was like a second home for the boy, who was homeschooled.
"It was a familiar place to him," he said. "I think if he did have in his mindset to do something foolish and start shooting people there also, I think his demeanor was tamed a little bit because he saw people there he knew."