As of June 19, 116 school shooting incidents were recorded in K-12 schools in the United States in 2025. Within the provided time period, the greatest number of K-12 school shootings was recorded in 2023, at 350. The source defines a school shooting as every time a gun is brandished, fired, or a bullet hits school property for any reason, regardless of the number of victims (including zero), time, day or the week, or reason, including gang shootings, domestic violence, shootings at sports games and after hours school events, suicides, fights that escalate into shootings, and accidents.

THIS DATASET WAS LAST UPDATED AT 8:11 AM EASTERN ON SEPT. 17

OVERVIEW

2019 had the most mass killings since at least the 1970s, according to the Associated Press/USA TODAY/Northeastern University Mass Killings Database.

In all, there were 45 mass killings, defined as when four or more people are killed excluding the perpetrator. Of those, 33 were mass shootings . This summer was especially violent, with three high-profile public mass shootings occurring in the span of just four weeks, leaving 38 killed and 66 injured.

A total of 229 people died in mass killings in 2019.

The AP's analysis found that more than 50% of the incidents were family annihilations, which is similar to prior years. Although they are far less common, the 9 public mass shootings during the year were the most deadly type of mass murder, resulting in 73 people's deaths, not including the assailants.

One-third of the offenders died at the scene of the killing or soon after, half from suicides.

About this Dataset

The Associated Press/USA TODAY/Northeastern University Mass Killings database tracks all U.S. homicides since 2006 involving four or more people killed (not including the offender) over a short period of time (24 hours) regardless of weapon, location, victim-offender relationship or motive. The database includes information on these and other characteristics concerning the incidents, offenders, and victims.

The AP/USA TODAY/Northeastern database represents the most complete tracking of mass murders by the above definition currently available. Other efforts, such as the Gun Violence Archive or Everytown for Gun Safety may include events that do not meet our criteria, but a review of these sites and others indicates that this database contains every event that matches the definition, including some not tracked by other organizations.

This data will be updated periodically and can be used as an ongoing resource to help cover these events.

Using this Dataset

To get basic counts of incidents of mass killings and mass shootings by year nationwide, use these queries:

Mass killings by year

Mass shootings by year

To get these counts just for your state:

Filter killings by state

Definition of "mass murder"

Mass murder is defined as the intentional killing of four or more victims by any means within a 24-hour period, excluding the deaths of unborn children and the offender(s). The standard of four or more dead was initially set by the FBI.

This definition does not exclude cases based on method (e.g., shootings only), type or motivation (e.g., public only), victim-offender relationship (e.g., strangers only), or number of locations (e.g., one). The time frame of 24 hours was chosen to eliminate conflation with spree killers, who kill multiple victims in quick succession in different locations or incidents, and to satisfy the traditional requirement of occurring in a “single incident.”

Offenders who commit mass murder during a spree (before or after committing additional homicides) are included in the database, and all victims within seven days of the mass murder are included in the victim count. Negligent homicides related to driving under the influence or accidental fires are excluded due to the lack of offender intent. Only incidents occurring within the 50 states and Washington D.C. are considered.

Methodology

Project researchers first identified potential incidents using the Federal Bureau of Investigation’s Supplementary Homicide Reports (SHR). Homicide incidents in the SHR were flagged as potential mass murder cases if four or more victims were reported on the same record, and the type of death was murder or non-negligent manslaughter.

Cases were subsequently verified utilizing media accounts, court documents, academic journal articles, books, and local law enforcement records obtained through Freedom of Information Act (FOIA) requests. Each data point was corroborated by multiple sources, which were compiled into a single document to assess the quality of information.

In case(s) of contradiction among sources, official law enforcement or court records were used, when available, followed by the most recent media or academic source.

Case information was subsequently compared with every other known mass murder database to ensure reliability and validity. Incidents listed in the SHR that could not be independently verified were excluded from the database.

Project researchers also conducted extensive searches for incidents not reported in the SHR during the time period, utilizing internet search engines, Lexis-Nexis, and Newspapers.com. Search terms include: [number] dead, [number] killed, [number] slain, [number] murdered, [number] homicide, mass murder, mass shooting, massacre, rampage, family killing, familicide, and arson murder. Offender, victim, and location names were also directly searched when available.

This project started at USA TODAY in 2012.

Contacts

Contact AP Data Editor Justin Myers with questions, suggestions or comments about this dataset at jmyers@ap.org. The Northeastern University researcher working with AP and USA TODAY is Professor James Alan Fox, who can be reached at j.fox@northeastern.edu or 617-416-4400.

This study provides an evidence-based understanding on etiological issues related to school shootings and rampage shootings. It created a national, open-source database that includes all publicly known shootings that resulted in at least one injury that occurred on K-12 school grounds between 1990 and 2016. The investigators sought to better understand the nature of the problem and clarify the types of shooting incidents occurring in schools, provide information on the characteristics of school shooters, and compare fatal shooting incidents to events where only injuries resulted to identify intervention points that could be exploited to reduce the harm caused by shootings. To accomplish these objectives, the investigators used quantitative multivariate and qualitative case studies research methods to document where and when school violence occurs, and highlight key incident and perpetrator level characteristics to help law enforcement and school administrators differentiate between the kinds of school shootings that exist, to further policy responses that are appropriate for individuals and communities.

The Washington Post spent a year determining how many children have been affected by school shootings, beyond just those killed or injured. To do that, reporters attempted to identify every act of gunfire at a primary or secondary school during school hours since the Columbine High massacre on April 20, 1999. Using Nexis, news articles, open-source databases, law enforcement reports, information from school websites, and calls to schools and police departments, The Post reviewed more than 1,000 alleged incidents, but counted only those that happened on campuses immediately before, during or just after classes. Shootings at after-hours events, accidental discharges that caused no injuries to anyone other than the person handling the gun, and suicides that occurred privately or posed no threat to other children were excluded. Gunfire at colleges and universities, which affects young adults rather than kids, also was not counted. After finding more than 200 incidents of gun violence that met The Post’s criteria, reporters organized them in a database for analysis. Because the federal government does not track school shootings, it’s possible that the database does not contain every incident that would qualify. To calculate how many children were exposed to gunfire in each school shooting, The Post relied on enrollment figures and demographic information from the U.S. Education Department, including the Common Core of Data and the Private School Universe Survey. The analysis used attendance figures from the year of the shooting for the vast majority of the schools. Credits: Research and Reporting: John Woodrow Cox, Steven Rich and Allyson Chiu Production and Presentation: John Muyskens and Monica Ulmanu Per the terms of the Creative Commons license, CISER notes that: 1. the license for this dataset is attached as the files license.htm and license.pdf. A brief version of the Creative Commons license is also included but users should familiarize themselves with the full license before using. 2. the licensed material is located at https://github.com/washingtonpost/data-school-shootings 3. Several of the files have been modified from the format presented at the above url including creating pdf versions of the documentation files and adding SAS, Stata, and SPSS versions through the use of StatTransfer 13. 4. These adapted versions of the original files are also released through the same Creative Commons license as the original with the same license elements.

This data comes from the Survey on Sexual Violence, 2006, an administrative records collection of incidents of inmate-on-inmate and staff-on-inmate sexual violence reported to correctional authorities. This dataset in particular focuses on allegations of staff-on-inmate sexual violence reported by State or Federal prison authorities by State. Between January 1 and June 30, 2007, BJS completed the third annual national survey of administrative records in adult correctional facilities, covering calendar year 2006. Although the results were limited to incidents reported to correctional officials, the survey provides an understanding of what officials know, based on the number of reported allegations, and the outcomes of follow-up investigations. By comparing results of the 2006 survey with those from 2004 and 2005, BJS is able to assess trends in sexual violence for the first time since the Act was passed. NV, NJ, NM, NC, RI: Reports of staff sexual misconduct may include reports of staff sexual harassment. TX: Reports of staff sexual harassment are not recorded in a central database. For more information on this data please go to: http://www.ojp.usdoj.gov/bjs/abstract/svrca06.htm

Founded in 1999, the Center for Homicide Research has made it its mission to increase case solvability and decrease the occurrence of homicide incidents. In working toward this goal, the Center has put together various databases of national homicide incidents. The Church Shooting Database uses online newspaper archive articles to document all cases of shootings on church property within the United States from 1980-2005. While extensive studies have been done exploring the details of other public shootings such as school campuses and workplaces, the phenomenon of shootings in churches has been left relatively untouched. Taking into account variables about the offenders, victims, and circumstances of each shooting, the database attempts to describe each incident as well as explore how the church context may play a role in the shooting.

Enclosed are data from CIESIN's Global subnational infant mortality rates database. Further documentation for these data is available in the enclosed catalog and on the CIESIN Poverty Mapping web site at: http://www.ciesin.columbia.edu/povmap Center for International Earth Science Information Network (CIESIN), Columbia University; 2005 Global subnational infant mortality rates [dataset]. CIESIN, Palisades, NY, USA. Available at: http://www.ciesin.columbia.edu/povmap/ds_global.html

DESCRIPTION Enclosed are data from CIESIN's Global subnational rates of child underweight status database. Further documentation for these data is available in the enclosed catalog and on the CIESIN Poverty Mapping web site at: http://www.ciesin.columbia.edu/povmap This is the beta release of this product. See the Poverty Mapping home page for additional information on the product. CITATION We recommend the following for citing the database: Center for International Earth Science Information Network (CIESIN), Columbia University; 2005 Global subnational rates of child underweight status [dataset]. CIESIN, Palisades, NY, USA. Available at: http://www.ciesin.columbia.edu/povmap/ds_global.html

This datasets displays the locations of all recorded earthquakes of a magnitude of 1 or greater around the world from the period of 6.30.08 to 7.7.08. The findings are from the US Geological Survey (USGS). Earthquake information is extracted from a merged catalog of earthquakes located by the USGS and contributing networks. Earthquakes will be broadcast within a few minutes for California events and within 30-minutes for world-wide events.

Ozone (O3) is a photochemical oxidant and the major component of smog. While O3 in the upper atmosphere is beneficial to life by shielding the earth from harmful ultraviolet radiation from the sun, high concentrations of O3 at ground level are a major health and environmental concern. The reactivity of O3 causes health problems because it damages lung tissue, reduces lung function and sensitizes the lungs to other irritants. Scientific evidence indicates that ambient levels of O3 not only affect people with impaired respiratory systems, such as asthmatics, but healthy adults and children as well. Title 40, Part 50 of the Code of the Federal Regulations lists the ambient air quality standards for ozone. Research and Innovative Technology Administration's Bureau of Transportation Statistics (RITA/BTS) Originator: Federal Highway Administration, Office of Planning, HEPP-1 Publication_Date: 2006 Title: Non-Attainment Areas: Ozone Geospatial_Data_Presentation_Form: vector digital data Publication_Information: Publication_Place: Washington, DC Publisher: Research and Innovative Technology Administration's Bureau of Transportation Statistics (RITA/BTS) Online_Linkage: Abstract: Non-attainment and maintenance areas for the United States and its territories. For more detailed information on this dataset, see the Overview Description in the Entity Attribute section of this document. Purpose: To establish the spatial boundaries of each nonattainment and maintenance area.

The map is based on data from Humanitarian Information Unit (HIU) of the U.S. State Dept. (http://hiu.state.gov/index.cfm?fuseaction=public.display&id=70216bae-d9e0-4c0b-9488-7a951375a99f There is a detailed explanation in the document that goes with the zipped dataset, titled: "Using Village Destruction Information Responsibly: February 27, 2007" that discusses the validity of the data. Surveillance of villages in Darfur, Sudan is an ongoing process. Much of the information already collected remains to be analyzed and confirmed. More information is also being collected. Unless a village appears to have sustained significant damage, it is considered undamaged (even though some structures may be damaged). A village labeled "Damaged" may have many destroyed structures just as a village labeled "Destroyed" may have a number of damaged structures among many destroyed ones. The categories simply hint at the extent of destruction (whether partial or nearly complete). For example, with the current data table (data as of January 25, 2007), we can map 1606 destroyed/damaged in the Darfur region. 411 villages are labeled as Damaged and 1195 villages are labeled as Destroyed. Several factors inhibit our ability to provide exact statistics for the number of structures destroyed/damaged. There are a number of confirmed and categorized villages for which there is no record of the number of structures. Additionally, in a few instances, a range for the number of structures destroyed or damaged was recorded. When the HIU receives further information on the status of more villages throughout the region, we will distribute it as appropriate.

This dataset looks at age and juvenile offender status as a means of restricting the purchase and possession of firearms in the USA as of 12.31.2005. This data displays the minimum age you must be to purchase/possess a handgun or a long gun in every state in the USA. It also displays if a state restricts juvenile offenders from purchasing/possessing a firearm, handguns or long guns. Also provided in the data is the statute within the States legislation that states the firearm purchase/possession restriction. Handgun: A firearm that has a short stock and is designed to be held and fired by the use of a single hand, such as a pistol or revolver. Long gun: A firearm with a barrel extended to around 30 inches to improve accuracy and range, and commonly with a shoulder butt, designed to be fired with two hands, such as a rifle or shotgun. This data comes from Survey of State Procedures Related to Firearm Transfers, 2005. The Survey provides an overview of the firearm check procedures in each State and State interaction with the National Instant Criminal Background Check System (NICS) operated by the FBI. The report summarizes issues about State procedures, including persons prohibited from purchasing firearms, restoration of rights of purchase to prohibited persons, permits, prohibited firearms, waiting periods, fees, and appeals. Supplemental tables contain data on 2005 applications to purchase firearms and rejections, as well as tabular presentations of State-by-State responses. This is one of a series of reports published from the BJS Firearm Inquiry Statistics (FIST) project, managed under the BJS National Criminal History Improvement Program (NCHIP). This is a web only document.

This data reports terror incidents involving IEDs recorded for Iraq in the National Counter Terrorism Center's World Wide Incident Tracking Database. It covers incidents that were observed for the first quarter of 2006. The Center cautions that there could be some incidents that have occurred in Iraq that are not in the data. Fatalities, wounded and hostages taken for each record are included in the data. Text descriptions and information on the perpetrators are also included in the file.

This data reports terror incidents involving IEDs recorded for Iraq in the National Counter Terrorism Center's World Wide Incident Tracking Database. It covers incidents that were observed for 2005. The Center cautions that there could be some incidents that have occurred in Iraq that are not in the data. Fatalities, wounded and hostages taken for each record are included in the data. Text descriptions and information on the perpetrators are also included in the file. Source: http://wits.nctc.gov/

This data reports terror incidents involving IEDs recorded for Iraq in the National Counter Terrorism Center's World Wide Incident Tracking Database. It covers incidents that were observed for the fourth quarter of 2004. The Center cautions that there could be some incidents that have occurred in Iraq that are not in the data. Fatalities, wounded and hostages taken for each record are included in the data. Text descriptions and information on the perpetrators are also included in the file.

This data reports terror incidents involving IEDs recorded for Iraq in the National Counter Terrorism Center's World Wide Incident Tracking Database. It covers incidents that were observed for the third quarter of 2005. The Center cautions that there could be some incidents that have occurred in Iraq that are not in the data. Fatalities, wounded and hostages taken for each record are included in the data. Text descriptions and information on the perpetrators are also included in the file.

This data reports terror incidents by Sunnis recorded for Iraq in the National Counter Terrorism Center's World Wide Incident Tracking Database. It covers incidents that were observed for the period 2004 up through March 2007. The Center cautions that there could be some incidents that have occurred in Iraq that are not in the data. Fatalities, wounded and hostages taken for each record are included in the data. The events in the database are those for which the perpetrator was known to be from the Sunni tribe. Source: http://wits.nctc.gov/

This data reports terror incidents recorded for Iraq in the National Counter Terrorism Center's World Wide Incident Tracking Database. It covers incidents that were observed for the period 2004 up through March 2007. The Center cautions that there could be some incidents that have occurred in Iraq that are not in the data. There are over 12,000 attacks for Iraq and the victims are of a variety of nationalities, American included. Fatalities, wounded and hostages taken for each record are included in the data. Source: http://wits.nctc.gov/

This data reports terror incidents involving firearms recorded for Iraq in the National Counter Terrorism Center's World Wide Incident Tracking Database. It covers incidents that were observed for the period 2004 up through March 2007. The Center cautions that there could be some incidents that have occurred in Iraq that are not in the data. Fatalities, wounded and hostages taken for each record are included in the data. Text descriptions and information on the perpetrator are also included in the data. Source: http://wits.nctc.gov/

This dataset explores Computer systems design and related services, by province as recorded by Statistics Canada. Notes: - North American Industry Classification System (NAICS), 2002 - 54151. - Estimates for the most recent year are preliminary. Preliminary data are subject to revision. Due to rounding, components may not add to total (where applicable). - Operating revenue excludes investment income, capital gains, extraordinary gains and other non-recurring items. - Operating expenses exclude write-offs, capital losses, extraordinary losses, interest on borrowing, and other non-recurring items. - Salaries, wages and benefits include vacation pay and commissions for all employees for whom a T4 slip was completed and the employer portion of employee benefits for items such as Canada/Qubec Pension Plan or Employment Insurance premiums. - Operating profit margin is derived as follows: operating revenue minus operating expenses, expressed as a percentage of operating revenue. Source: Statistics Canada, CANSIM, table (for fee) 354-0005 and Catalogue no. 63-018-X. Last modified: 2008-05-23.