NEWTOWN, Conn. — The 1,500 documents released by the FBI on Tuesday about the investigation into the deadly shootings at Sandy Hook Elementary School in Newtown included disturbing new details on the shooter.
The report, which was posted online just weeks before the fifth anniversary of the shootings, said that a Newtown resident had warned police that Adam Lanza had threatened to kill his mother and students, according to CBS News.
Lanza killed his mother while she slept in their home on Dec. 14, 2012, then went to the school, where he killed 20 first-graders and six educators before turning a gun on himself.
Large sections of the documents, which included interviews by FBI agents with people who knew Lanza, were redacted. The FBI had convened a grand jury after the shooting to investigate.
But in one section, a woman said she had overheard Lanza threaten his mother and that he "had an assault weapon and that she was scared of him," CBS News said. She reported that Lanza said he "planned to kill his mother and children at Sandy Hook."
The woman called Newtown police and Sandy Hook, but police said Lanza's mother owned the firearms and there was nothing they could do, CBS News said.
Another unidentified person said that Nancy Lanza had become concerned about her son, who had become a shut-in and had not left the house in three months, CBS News said.
The FBI profile of Adam Lanza, one of the documents released, said the shooter had carefully planned the deadly shootings for 21 months, according to the Hartford Courant.
One neighbor said that FBI agents had visited the Lanza home when Adam was in ninth grade because he had hacked into a government computer system, the Courant said.
There was also an interview with a woman who began communicating online with Lanza after spotting his postings about the Columbine school shooting, the Courant said. Lanza told her how he created a spreadsheet of details of mass killings and shooting sprees. Though the communicated about once a month, she did not know Lanza’s name or where he lived, the Courant said.
Lanza was “the most fixated and disturbed Internet associate she had ever encountered,” she told the FBI.
After learning of Lanza’s attack, the woman told the FBI that Lanza was “more (expletive) up than I thought.”
Click here to read the FBI files.
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