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Crime & Justice • Mass Shooting

Adam Lanza

Adam Lanza was an American mass murderer who carried out the Sandy Hook Elementary School shooting in Newtown, Connecticut, on 14 December 2012.

By Ethan Anderson| Reviewed by Olivia Bennett, Standards & Fact-Checking Lead| Updated July 26, 2026|2 min read| Fact-checked

Adam Lanza was an American mass murderer who carried out the Sandy Hook Elementary School shooting in Newtown, Connecticut, on 14 December 2012. Before the school attack, he killed his mother, Nancy Lanza, at their home, and then died by suicide at the school. The shooting killed 20 children and 6 adult staff members, making it one of the deadliest mass shootings in United States history.

Background

Adam Lanza was born in 1992 in Kingston, New Hampshire, and lived in Newtown, Connecticut. Public reporting describes him as a reclusive young man, though many details of his private life remain disputed or incomplete.

Sandy Hook Elementary School shooting

On 14 December 2012, Lanza killed his mother and then attacked Sandy Hook Elementary School in Newtown, Connecticut. The shooting left 26 victims at the school, including 20 children and 6 adults, before Lanza died by suicide.

Aftermath and investigation

The massacre prompted extensive law-enforcement investigation and sustained public debate about firearms, school safety, and mental health. Official reports said he acted alone and did not establish a single definitive motive.

Public profile

Media coverage of Lanza focused heavily on his behavior, interests, and possible psychological issues. Reporting also noted his documented fascination with previous mass shootings, including Columbine.

Key facts

  • Adam Lanza was identified as the perpetrator of the Sandy Hook Elementary School shooting on 14 December 2012.
  • He killed his mother, Nancy Lanza, at their home in Newtown, Connecticut, before going to the school.
  • At Sandy Hook Elementary School, he killed 20 children and 6 adult staff members.
  • Lanza died by suicide as law enforcement arrived at the school.
  • The attack is widely described as one of the deadliest mass shootings in U.S. history.
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Canadian context

The Sandy Hook shooting drew major media coverage in Canada and influenced Canadian discussions about school safety, gun violence, and public policy.

Frequently asked questions

Who was Adam Lanza?
Adam Lanza was the perpetrator of the Sandy Hook Elementary School shooting in Newtown, Connecticut, in 2012.
What happened at Sandy Hook?
Lanza killed 20 children and 6 adult staff members at the school after killing his mother earlier the same day.
Did Adam Lanza die at the scene?
Yes. He died by suicide at the school as law enforcement arrived.
Where was Adam Lanza born?
He was born in Kingston, New Hampshire, in the United States.
Why did Adam Lanza carry out the attack?
Investigators did not establish a definitive motive.

References

  1. Encyclopaedia Britannicahttps://www.britannica.com/biography/Adam-Lanza
    Supports: Biographical identification, date of death, and description of the Sandy Hook attack.
  2. CNNhttps://www.cnn.com/us/connecticut-shootings-fast-facts
    Supports: Basic biographical facts and the sequence of events on 14 December 2012.
  3. BBC Newshttps://www.bbc.com/news/world-us-canada-25097127
    Supports: Official-report findings on his interest in Columbine and the lack of a confirmed motive.
  4. BBC Newshttps://www.bbc.com/news/world-us-canada-20738732
    Supports: Background coverage of Lanza and the Sandy Hook shootings.