Credit: CBS News
Dec. 14, 2012: A gunman at a Sandy Hook Elementary School in Newtown, Conn. killed 27 people, including 20 children. The attack appeared to be the nation's second-deadliest school shooting, exceeded only by the Virginia Tech massacre in 2007. Pictured: In this photo provided by the Newtown Bee, Connecticut State Police lead children from the Sandy Hook Elementary School following the shooting.
Credit: AP Photo/Newtown Bee, Shannon Hicks