The Sandy Hook Elementary School shooting occurred on December 14, 2012, in Newtown, Connecticut, when 20-year-old Adam Lanza fatally shot 20 children and 6 adult staff members. Prior to driving to the school, Lanza shot and killed his mother at their Newtown home. As first responders arrived at the scene, Lanza committed suicide by shooting himself in the head.
The incident was the deadliest mass shooting at a high school or grade school in U.S. history and the second-deadliest mass shooting by a single person in U.S. history, after the 2007 Virginia Tech shootings. The shooting prompted renewed debate about gun control in the United States, including proposals for making the background-check system universal, and for new federal and state legislation banning the sale and manufacture of certain types of semi-automatic firearms and magazines with more than ten rounds of ammunition. A November 2013 report issued by the Connecticut State Attorney's office concluded that Lanza acted alone and planned his actions, but no evidence collected provided any indication as to why he did so, or why he targeted the school.