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Columbine High School shooting

The Columbine High School shooting was a mass shooting at Columbine High School in Littleton, Colorado, on April 20, 1999.

By Ethan Anderson| Reviewed by Olivia Bennett, Standards & Fact-Checking Lead| Updated September 11, 2026|2 min read| Fact-checked

The Columbine High School shooting was a mass shooting at Columbine High School in Littleton, Colorado, on April 20, 1999, carried out by students Eric Harris and Dylan Klebold. The perpetrators killed 12 students and one teacher, wounded 23 others, and then died by suicide. At the time, it was the deadliest high school shooting in U.S. history.

Background

Columbine High School is located in Littleton, Colorado, a suburb of Denver. The school became internationally known because of the 1999 shooting and the extensive media and public attention that followed.

The shooting

According to the sources, Harris and Klebold entered the school armed with firearms and explosives and began the attack around 11:19 a.m. Their original plan involved bombs, but the attack ultimately unfolded as a school shooting.

Casualties

The attack killed 12 students and one teacher, with the two perpetrators later dying by suicide. The sources report 23 wounded, though some secondary accounts give slightly different injury totals.

Legacy

The Columbine shooting became a reference point in discussions of school security, youth violence, and gun policy in the United States. It is frequently cited as a turning point in how school shootings are covered and analyzed.

Key facts

  • The attack occurred on April 20, 1999, at Columbine High School in Littleton, Colorado.
  • Perpetrators Eric Harris and Dylan Klebold killed 12 students and one teacher before dying by suicide.
  • 23 people were wounded in the attack.
  • The shooting prompted national debate on school safety and gun violence.
  • It was the deadliest high school shooting in the U.S. until 2018.
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Canadian context

The Columbine shooting influenced Canadian discussions of school safety, emergency response, and gun-violence prevention, and it is often referenced in Canadian media and policy debates about school shootings.

Frequently asked questions

When did the Columbine High School shooting happen?
It happened on April 20, 1999.
Where did the shooting take place?
It took place at Columbine High School in Littleton, Colorado, United States.
Who carried out the attack?
The perpetrators were Eric Harris and Dylan Klebold, both students at the school.
How many people were killed?
Thirteen victims were killed, and the two perpetrators also died by suicide, making 15 deaths in total.
How many people were injured?
The sources used here report 23 wounded.
Why is Columbine historically significant?
It was one of the deadliest school shootings in U.S. history and, at the time, the deadliest high school shooting in the country.

References

  1. CNNhttps://www.cnn.com/us/columbine-high-school-shootings-fast-facts
    Supports: Date, perpetrators, deaths, injuries, and basic chronology of the attack.
  2. Encyclopaedia Britannicahttps://www.britannica.com/event/Columbine-High-School-shootings
    Supports: Location, date, perpetrators, fatalities, injuries, and historical significance.
  3. Federal Bureau of Investigationhttps://vault.fbi.gov/Columbine%20High%20School%20
    Supports: Official summary of the incident and investigation.
  4. HISTORYhttps://www.history.com/articles/columbine-high-school-shootings
    Supports: Timeline, sequence of events, and casualties.
  5. Crime Museumhttps://www.crimemuseum.org/crime-library/mass-murder/columbine-shooting/
    Supports: Attack planning, weapons, and broader impact.
  6. Wikipediahttps://www.wikipedia.org/wiki/Columbine_High_School
    Supports: Historical note that the shooting was later surpassed as the deadliest high school shooting in the U.S.