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Boston Marathon bombing

The Boston Marathon bombing was a terrorist attack that occurred near the finish line of the Boston Marathon in Boston, Massachusetts, on April 15, 2013.

By Ethan Anderson| Reviewed by Olivia Bennett, Standards & Fact-Checking Lead| Updated July 27, 2026|2 min read| Fact-checked

The Boston Marathon bombing was a terrorist attack that occurred near the finish line of the Boston Marathon in Boston, Massachusetts, on April 15, 2013. Two pressure-cooker bombs detonated seconds apart, killing three people and injuring hundreds more. The attack led to a major manhunt, the death of one suspect, and the conviction of the surviving suspect, Dzhokhar Tsarnaev.

Attack

Two homemade explosives detonated near the marathon finish line on Boylston Street during the afternoon of April 15, 2013. The blasts caused deaths, severe injuries, and immediate disruption to the race and surrounding area.

Investigation and manhunt

Authorities identified the Tsarnaev brothers as suspects after reviewing surveillance footage and other evidence. After a confrontation with police and a citywide search, Tamerlan Tsarnaev died and Dzhokhar Tsarnaev was arrested.

Dzhokhar Tsarnaev was charged with multiple federal crimes, including use of a weapon of mass destruction resulting in death. A jury convicted him on all counts, and he was sentenced to death in 2015.

Casualties and response

The bombing killed three people and injured hundreds, including several who suffered amputations. Emergency responders, hospitals, and law-enforcement agencies carried out a large-scale mass-casualty response.

Key facts

  • The bombing occurred during the 117th Boston Marathon on April 15, 2013.
  • Two bombs exploded near the finish line, killing three people and injuring hundreds.
  • The attack was carried out by the Tsarnaev brothers, who acted without known organizational affiliation.
  • A large manhunt followed; Tamerlan Tsarnaev died after a shootout, and Dzhokhar Tsarnaev was captured alive.
  • Dzhokhar Tsarnaev was later convicted on 30 federal counts and sentenced to death.
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Canadian context

The bombing was widely covered in Canada and drew attention because of its impact on a major North American sporting event, its cross-border media coverage, and its significance in discussions of terrorism and public safety.

Frequently asked questions

What was the Boston Marathon bombing?
It was a terrorist attack in Boston on April 15, 2013, when two bombs exploded near the marathon finish line, killing three people and injuring hundreds.
Who carried out the attack?
The attack was carried out by brothers Tamerlan Tsarnaev and Dzhokhar Tsarnaev.
How many people were killed?
Three people were killed in the bombing.
How many people were injured?
Sources report more than 260 injuries, and some accounts say more than 500 people were physically injured.
What happened to the suspects?
Tamerlan Tsarnaev died after a shootout with police during the manhunt, and Dzhokhar Tsarnaev was arrested, convicted, and sentenced to death.
Was the attack linked to a terrorist group?
Available sources describe the Tsarnaev brothers as acting without known organizational affiliation or confirmed ties to a terrorist group.

References

  1. Encyclopaedia Britannicahttps://www.britannica.com/event/Boston-Marathon-bombing-of-2013
    Supports: Date, location, fatalities, and general description of the attack
  2. Federal Bureau of Investigationhttps://www.fbi.gov/history/famous-cases/boston-marathon-bombing
    Supports: Perpetrators, investigation, casualty figures, and conviction details
  3. CNNhttps://www.cnn.com/us/boston-marathon-terror-attack-fast-facts
    Supports: Timing of explosions, casualty figures, terrorism designation, and sentencing
  4. HISTORYhttps://www.history.com/articles/boston-marathon-bombing-timeline
    Supports: Attack timeline, suspects, manhunt, and legal outcome