Why Adam Lanza went on his murderous shooting rampage at a Newtown elementary school is a mystery and may never be known, prosecutors said in a report Monday as they closed their yearlong ... more 
Why Adam Lanza went on his murderous shooting rampage at a Newtown elementary school is a mystery and may never be known, prosecutors said in a report Monday as they closed their yearlong investigation. less 
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Mon, Nov 25, 2013 6:40 PM EST