Direct answer: how many people did the Boston bombers kill
Three people were killed and hundreds were injured in the Boston Marathon bombing on April 15, 2013. The attackers were two brothers, Tamerlan Tsarnaev and Dzhokhar Tsarnaev, who placed pressure cooker bombs near the finish line. The fatalities and verified casualty details are outlined below, based on official investigations and court records.
Victim names and basic context
| Victim | Verified detail | Source type |
|---|---|---|
| Martin Richard | Killed; 8-year-old boy | Official reports / Coroner |
| Krystle Campbell | Killed; 29-year-old woman | Official reports / Coroner |
| Lingzi Lu | Killed; 23-year-old graduate student | Official reports / Coroner |
| Sean Collier | Killed; MIT police officer (not a marathon runner) | Official reports / Coroner |
Note: The widely reported fatality count for the Marathon bombing itself is three. A fourth victim, MIT Police Officer Sean Collier, was killed in a separate incident during the manhunt. Official inquiries, including the U.S. Department of Justice and the Boston Marathon Victim Assistance Fund, confirm these numbers.
Who were the bombers
The perpetrators were Tamerlan Tsarnaev (26 at the time) and his younger brother Dzhokhar Tsarnaev (19). They were ethnic Chechen immigrants raised in the United States. Investigations concluded they were inspired by extremist ideology disseminated online and acted alone in planning the attack. Tamerlan died during a shootout and VBIED explosion while attempting to escape custody; Dzhokhar was apprehended, tried, and convicted.
Attack timeline and verified details
The bombing occurred near the finish line of the Boston Marathon on April 15, 2013, at approximately 2:49p.m. local time. Two pressure cooker bombs detonated within seconds of each other, causing blast and fragmentation injuries. The subsequent manhunt involved a multi-agency response, a citywide lockdown, and an exchange of gunfire with law enforcement. Courts have documented the attack’s planning, evidence, and victim impact.
Casualty summary by category
| Category | Metric | Count | Context |
|---|---|---|---|
| Immediate fatalities | Marathon bombing victims | 3 | Runners and spectators at the finish area |
| Additional fatality | Law enforcement killed during manhunt | 1 | MIT Officer Sean Collier |
| Injuries | Confirmed injured (civilian and responder) | Approximately 260–320 | Includes amputations, shrapnel wounds, and trauma |
| Perpetrators | Confirmed attackers | 2 | Tamerlan and Dzhokhar Tsarnaev |
A note on sources
Numbers above are drawn from U.S. government reports, coroner records, court filings, and victim assistance databases. Where ranges are provided (e.g., injured), they reflect documented variations across official summaries. Ongoing civil litigation and victim services updates may refine non-fatal injury counts, but the three civilian fatalities and additional officer fatality are not in dispute.
Evergreen context and terminology
The event is commonly referred to as the Boston Marathon bombing or the 2013 Boston Marathon attack. It is distinct from other incidents during the 2013 manhunt. Understanding the basic facts—fewer than four direct fatalities from the bombing itself, with a broader set of injuries and related deaths during the response—is useful for accurate reference, education, and informed discussion.