A mass shooting at Sandy Hook Elementary School in Newtown, Conn. left 27 people dead, including 20 children and the gunman, on Dec. 14, 2012. The gunman, identified as 20-year-old Adam Lanza, reportedly had three guns on him, including an AR-15 semiautomatic rifle. Lanza killed himself in the school. After the shooting, it was discovered that Lanza had also shot and killed his mother, Nancy Lanza, in the home they shared.
Author: Edecio Martinez, Julia Dahl
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