The Newtown school massacre was the result of a lethal combination of gunman Adam Lanza's mental health issues, access to high-powered weapons and an obsession with mass murders, a nearly year-long investigation concluded.
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But the report released today did not say why Lanza targeted the Sandy Hook elementary school, other than its proximity to his home.
The report offered the first official account of the Dec. 12, 2012, shooting that killed 27 people, mostly young students.
Lanza used a stockpile of weapons and ammunition purchased by his mother to commit the crimes, which included killing his mother at their home, then driving to Sandy Hook and killing 20 students and six staffers.
The report also detailed the items found in Lanza's bedroom, including news articles about other school shootings, video games including "Left for Dead" and "Call of Duty," and photographs of a person covered in blood.
The report was unable to "establish a conclusive motive," but said, "What we do know is that the shooter had significant mental health issues that ... did affect his ability to live a normal life and interact with others," the report said.
It added that Lanza had "access to firearms and ammunition and an obsession with mass murders, in particular the Columbine shootings."
The report was released just shy of one year after the shooting, on the same day Connecticut Superior Court Judge Eliot Prescott said that he would listen to all of the 911 calls from the day of the shooting and decide whether to release them to the public.
Few details about what actually happened in the Sandy Hook school that day, and about the background and possible motives of Lanza, have been released to the public.
Now, just weeks before the anniversary of the shooting, Newtown parents and community members braced themselves for the release of information about the gruesome day.
"We are gearing up for the release of the investigation report, will learn of the disposition of the tapes of the 911 calls, and will experience the first anniversary of the tragedy at Sandy Hook School," Newtown council member Pat Llodra wrote on her blog this week. "Each of these happenings has the potential to feel like a body blow. It takes our breath away, and we struggle to regain our balance."
Llodra said that over the past year, unofficial leaks of information that had been reported have been painful for the community.
"We cannot stop the drip-drip-drip of leaked information -- a problem that has plagued us for months and months. Is it possible that those persons who feel compelled to speak without authority and without permission do not know the harm they do?"
"And we cannot stop the release of whatever information the courts determine must be released. And we cannot, despite massive efforts of many, ensure that we will not be overrun by media on Dec. 14," she said.
Llodra emphasized that though the anniversary will once again draw attention and a media presence to Newtown, the town will hold no public memorials on Dec. 14 and will choose, instead, to remember the tragedy quietly.
"So, what can we do? We can tap into that inner strength we have called upon again and again over this past year to confront what we must, manage that hurt as best we can, and put it behind us somehow," she said. "We have a choice on Dec.14. We have called upon every person to honor those who lost their lives that day in a personal, kind way."