By Beth Stebner PUBLISHED: 13:17 EST, 19 February 2013 | UPDATED: 05:52 EST, 20 February 2013 Adam Lanza, the young man who grow up to kill 27 people, including 20 school children and his own mother, is seen for the first time as a four-year-old boy in a family video. In home video obtained exclusively by the Hartford Courant and PBS’ Frontline, a young Lanza is seen in 1996 at a police demonstration with the Scouts. The young Lanza wanders through the woods as his mother, Nancy, tells him off camera to bark like a dog, imitating the dog barks around him.
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Adam Lanza killed 27 people in Connecticut, including 20 school children and his own mother, Nancy Lanza
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New Frontline/Hartford Courant video shows four-year-old Lanza in 1996
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Anders Breivik murdered 77 in Norway in 2011; eight in a car bombing in the capital and 69 more at a summer camp
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Police probing whether Lanza may have been a copying video game as he went room-to-room firing a Bushmaster assault rifle at the school
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He smashed his hard drive before the massacre, making his online trail and habits impossible to follow
Victims: Top row, left to right; Ana Marquez-Greene, Caroline Previdi, Jessica Rekos, Emilie Parker, @placeholder.