Crime & Justice • Mass shooting

Sandy Hook Elementary School shooting

The Sandy Hook Elementary School shooting was a mass shooting that took place in Newtown, Connecticut, on December 14, 2012.

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

The Sandy Hook Elementary School shooting was a mass shooting that took place in Newtown, Connecticut, on December 14, 2012. Adam Lanza killed 20 children and 6 adults at the school after also killing his mother earlier that day, then died by suicide at the scene. It is widely regarded as one of the deadliest school shootings in U.S. history.

Background

The shooting took place at Sandy Hook Elementary School in Newtown, Connecticut, on December 14, 2012. Investigations identified Adam Lanza as the perpetrator.

The attack

Earlier that day, Lanza killed his mother at their home. He then entered the school and killed 20 children and 6 adult staff members before dying by suicide. Two additional people were injured in the incident.

Aftermath

The shooting led to intense public attention and policy debate in the United States. It also became associated with later investigations, legal actions, and advocacy work connected to gun violence prevention.

Legacy

Sandy Hook is frequently cited in discussions of school security, mass shootings, and gun-control policy. It also remains a highly significant event in contemporary U.S. public memory.

Key facts

The attack occurred at Sandy Hook Elementary School in Newtown, Connecticut, on December 14, 2012.
Adam Lanza killed 20 children and 6 adult staff members at the school.
Lanza also killed his mother earlier that day and died by suicide after the attack.
The shooting was among the deadliest school shootings in U.S. history.
The event prompted national debate over gun violence, school safety, and mental health.

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Canadian context

The shooting is relevant to Canadian readers as a major North American mass-casualty event that influenced international discussion of school security, gun regulation, trauma response, and public policy.

Frequently asked questions

What was the Sandy Hook Elementary School shooting?

It was a mass shooting at Sandy Hook Elementary School in Newtown, Connecticut, on December 14, 2012, in which 20 children and 6 adults were killed.

Who carried out the shooting?

The perpetrator was Adam Lanza.

How many people died?

Twenty-six people were killed at the school, and Lanza later died by suicide. He also killed his mother earlier that day.

How many children were killed?

Twenty children, all between six and seven years old, were killed.

Why is the event historically significant?

It is one of the deadliest school shootings in U.S. history and became a major reference point in debates over gun violence and school safety.

References

Britannica — https://www.britannica.com/event/Sandy-Hook-Elementary-School-shooting
Supports: Date, location, fatalities, injuries, perpetrator, and significance
CNN — https://www.cnn.com/us/connecticut-shootings-fast-facts
Supports: Perpetrator, victim counts, and sequence including the killing of Lanza's mother
State of Connecticut — https://portal.ct.gov/-/media/Malloy-Archive/Sandy-Hook-Advisory-Commission/SHAC_Final_Report_3-6-2015.pdf
Supports: Official account of deaths, injuries, and event description
State of Connecticut — https://portal.ct.gov/-/media/DCJ/SandyHookFinalReportpdf.pdf
Supports: Official investigative findings and weapon details
Britannica — https://www.britannica.com/place/United-States/The-Sandy-Hook-Elementary-School-shooting
Supports: National impact and policy debate in the United States