Final Newtown, Conn., Shooting Report Leaves Big Question Unanswered

Report reveals details of Adam Lanza's solitary life but did not identify a "conclusive" motive.
3:00 | 11/25/13

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Transcript for Final Newtown, Conn., Shooting Report Leaves Big Question Unanswered
We move to new clues about the mind of a mad man, adam lanza, the gunman at sandy hook. One year later why he did it is a mystery. Officials have been scouring every corner of his life for answers and tonight they reveal what they found. Abc's chief investigative correspondent brian ross has the details. Caller is indicating she thinks someone is shooting in the building. Reporter: Today's report said it took only 11 minutes for the shooter to kill all 20 first graders and six adults in the school. As to why 20-year-old adam lanza targeted the school, the state prosecutor said his investigation does not establish a conclusive motive. For the first time officials released photos taken inside his home where he had first killed his mother. There was a shooting range target with holes in it, video games that authorities say he spent hours playing, an open gun safe with a teddy bear on top and news clippings dating back TO THE 1890s SHOWING AN Obsession with mass murders, in particular the columbine shootings. He was thinking about committing this crime. Reporter: Police also found a shattered computer hard drive that lanza destroyed. Officials were able to recover e-mails that he exchanged with others who were interested in the topic of mass shootings. School shooters do this these because it empowers them. Reporter: Out of consideration of the families, other material that might ordinarily be made public is still withheld including 911 calls and photos of the victims. Nicole hockly talks with laura spencer. What parent would want that. It's not the way I want dylan to be remembered. Reporter: The report says lanza had significant mental health issues and in the end only communicated with his mother by e-mail. But the prosecutor concluded that he was well enough to plan the attack including the taking of his own life all with guns legally purchased by his mother. Not far from newtown today another gun scare at yale

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