Over the last few years, gun violence in the United States has become an increasingly deadly public health crisis. In 2021, firearms were the leading cause of death for children and adolescents aged one to 19 years old for a second year in a row in the United States, with ***** deaths from firearms, which accounted for more deaths than car crashes and other diseases in that year. This is an increase from the previous year, when there were ***** deaths from firearms. Gun violence in the U.S. Along with a rise in gun-related deaths, the United States has been experiencing an overall increase in gun violence, including mass shootings, school shootings, and gun homicides. Not surprisingly, the United States has also reported in increase in gun sales, with the unit sales for firearms reaching a new high in recent years. A uniquely American problem Despite the rise of gun violence and gun-related deaths, guns remain easily accessible in the United States and gun control has become a divisive issue throughout the nation. However, gun control proponents often call attention to the uniquely American phenomenon of school shootings. Since 2018, the annual number of incidents involving firearms at K-12 schools in the U.S. reached over *** in each year, while similar incidents in other countries with strict gun laws are exceptionally rare.

THIS DATASET WAS LAST UPDATED AT 8:11 PM EASTERN ON AUG. 30

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.

As of August 11, 14 people were killed in mass shootings in the United States in 2025. A total of 1,173 victims were fatally injured during mass shootings in the United States between 1982 and August 11, 2025.

The deadliest school shooting in the United States as of August 11, 2025, was the Virginia Tech massacre, with 32 fatalities and 23 injuries. The next deadliest school shooting (based on fatalities) was the Sandy Hook Elementary massacre in Newtown, Connecticut, with 27 fatalities. School shootings in the U.S. Mass shootings in the United States have become a disturbingly common occurrence, and sadly, so have school shootings. The Columbine school shooting is perhaps the most famous in the country’s history, and since 1999 (when the shooting occurred), the number of school shootings has only increased. Many measures have been used to try to prevent school shootings, including security guards and metal detectors being deployed in schools, and even the suggestion that teachers be allowed to carry guns in schools. Gun control Gun control in the United States is a sticky issue, since gun ownership is enshrined in the Constitution. Some advocate for stricter gun control laws to try to prevent future mass shootings, while others say that this is unconstitutional. Gun ownership rates in the U.S. are high, with the share of American households owning at least one firearm remaining relatively steady since 1972.

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.

As of March 19, ***** school shootings were recorded in the United States in 2025, impacting K-12 school grounds and college campuses nationwide. In comparison, there were ** school shooting incidents recorded in 2024. In addition to schools, gun-related violence occurs in many public places within the United States, including workplaces, churches, restaurants, and nightclubs. The source defines school shootings as incidents of gun violence which occurred on school property and at least one person was shot, not including the shooter. School property includes, but is not limited to, buildings, fields, parking lots, stadiums and buses. Accidental discharges of firearms are included, as long as at least one person is shot, but not if the sole shooter is law enforcement or school security.

Number and percentage of homicide victims, by type of firearm used to commit the homicide (total firearms; handgun; rifle or shotgun; fully automatic firearm; sawed-off rifle or shotgun; firearm-like weapons; other firearms, type unknown), Canada, 1974 to 2018.

Number of homicide victims, by method used to commit the homicide (total methods used; shooting; stabbing; beating; strangulation; fire (burns or suffocation); other methods used; methods used unknown), Canada, 1974 to 2024.

In 2019, ** children younger than one year died due to firearms in the United States. In that same year, ***** people between the ages of 25 and 34 years old died and ***** people between the ages of 45 and 54 years old died due to firearms across the country.

As of June 2022, there were 153 school shootings in total in the United States in that year. Of these incidents, only two were active shooter incidents. The largest number of active shooter incidents in schools was in 2018, with 11 active shooters.

The source defines a shooting as any time a gun is brandished, fired, or a bullet hits school property for any reason.

In 2023, there were ****** fatalities caused by injuries related to firearms in the United States, a slight decrease from the previous year. In 2021, there were ****** firearm deaths, the highest number of gun deaths ever recorded in the country. However, this figure has remained relatively high over the past 25 years, with ****** firearm deaths in 1990 and a slight dip in fatalities between 1999 and 2002. Firearms in the United States The right to own firearms in the United States is enshrined in the 2nd Amendment of the U.S. Constitution, and while this right may be seen as quintessentially American, the relationship between Americans and their firearms has become fraught in the last few years. The proliferation of mass shootings in the U.S. has brought the topic of gun control into the national spotlight, with support for banning assault-style weapons a particularly divisive issue among Americans. Gun control With a little less than **** of all Americans owning at least one firearm and the highest rate of civilian gun ownership in the world, it is easy to see how the idea of gun control is a political minefield in the U.S. However, public opinion has begun to shift over the past ten years, and a majority of Americans report that laws governing the sale of firearms should be stricter than they are now.

In 2023, a total of 187 child fatalities due to abuse or maltreatment occurred in Texas, the most out of any state. In that year, California, Ohio, New York, and North Carolina rounded out the five leading states for child abuse deaths.

From 1999 to January 2025, *** school shootings were recorded in the United States, *** of which occurred in public schools. Within the provided time period, only ** shootings were recorded in private schools.

In 2023, around 2,444 homicide victims in the United States were aged between 20 and 24 years old. A further 2,362 murder victims were between the ages of 30 and 34 years old. Most murder victims in the United States in 2023 were between the ages of 17 and 54 years old.

In the United States, Black people have higher rates of gun homicide than White people across all age groups. As of 2022, gun homicide rates were highest among Black people aged between 15 and 24 years, at ***** gun homicides per 100,000 of the population. In comparison, there were only **** gun homicides per 100,000 of the White population within this age range. However, the risk for gun homicide was greatest among all adolescents and adults between the ages of 15 to 44 in that year. The impact of guns on young Americans In the last few years, firearms have become the leading cause of death for American children and teenagers aged one to 19 years old, accounting for more deaths than car crashes and diseases. School shootings also remain on the rise recently, with the U.S. recording ** times as many school shootings than other high-income nations from 2009 to 2018. Black students in particular experience a disproportionately high number of school shootings relative to their population, and K-12 teachers at schools made up mostly of students of color are more likely to report feeling afraid that they or their students would be a victim of attack or harm. The right to bear arms Despite increasingly high rates of gun-related violence, gun ownership remains a significant part of American culture, largely due to the fact that the right to bear arms is written into the U.S. Constitution. Although firearms are the most common murder weapon used in the U.S., accounting for approximately ****** homicides in 2022, almost **** of American households have at least one firearm in their possession. Consequently, it is evident that firearms remain easily accessible nationwide, even though gun laws may vary from state to state. However, the topic of gun control still causes political controversy, as the majority of Republicans agree that it is more important to protect the right of Americans to own guns, while Democrats are more inclined to believe that it is more important to limit gun ownership.

Between 1970 and June 16, 2020, 175 school shootings were perpetrated by 17-year-olds. 16-year-olds perpetrated the second highest number of school shootings, with 163 shootings.

Handguns are by far the most common murder weapon used in the United States, accounting for 7,159 homicides in 2023. This is followed by firearms of an unstated type, with 5,295 cases in that year. Why do murders happen in the U.S.? While most of the time the circumstances of murders in the U.S. remain unknown, homicides due to narcotics come in as the second most common circumstance – making them more common than, for example, gang killings. Despite these gruesome facts, the violent crime rate has fallen significantly since 1990, and the United States is much safer than it was in the 1980s and 1990s. Knife crime vs disease: Leading causes of death The death rate in the U.S. had hovered around the same level since 1990 until there was a large increase due to the COVID-19 pandemic in recent years. Heart disease, cancer, and accidents were the three leading causes of death in the country in 2022. The rate of death from heart disease is significantly higher than the homicide rate in the United States, at 167.2 deaths per 100,000 population compared to a 5.7 homicides per 100,000. Given just 1,562 murders were caused by knife crime, it is fair to say that heart disease is a far bigger killer in the U.S.

In recent years there has been an increase in the rate of firearm-related deaths in the United States. In 2021, there were **** such deaths per 100,000 population. This is the highest rate seen since the early *****. Firearm deaths Firearm-related deaths are much more common among males than females, with almost ****** firearm deaths among males in the United States in 2021, compared to just ****** among females. Those aged 25 to 34 years are the age group with the highest number of deaths from firearms, followed by those aged 15 to 24. The states with the highest mortality rates from firearms are Mississippi, Louisiana, and Wyoming. Firearm suicides The use of firearms is one of the most common methods for suicide in the United States. Around ** percent of male suicides and ** percent of female suicides are conducted by firearms. In 2020, there were a total of ****** suicide deaths from firearms. Suicide is currently the **** leading cause of death in the United States.

In 2024, a total of ****** homicides were registered in Mexico, over 1.1** murder victims more than the death toll reported a year earlier. The number of homicides in Mexico, including intentional homicides and cases of manslaughter, grew between 2015 and 2018, before plateauing around ****** victims per year. Kidnapping in Mexico In Mexico, even with a ** percent reduction in the kidnapping rate, which amounted to *** reported cases in 2023, the region continues to witness the distressing reality of **** individuals being subjected to violent abduction daily. These heinous acts are chiefly perpetrated in various settings, including workplaces, residences, and public areas. Furthermore, the state with the highest recorded kidnapping incidence is Mexico State, marking a significant disparity in numbers. This dire situation positions the country as the third highest in terms of kidnapping occurrences throughout Latin America. The increasing cases of human trafficking Regarded as a grievous form of exploitation encompassing coerced labor or sexual servitude, the prevalence of human trafficking in the nation exhibits a disquieting escalation. This trend coincides with a decline in cases involving children, shifting the focus towards teens and adolescents, particularly females, who are now the primary target demographic. Perpetrators manipulate victims through deceitful practices and fraudulent schemes, effectively entrapping them in a web of organized criminal activities that deprive them of their freedom.

The rate of fatal police shootings in the United States shows large differences based on ethnicity. Among Black Americans, the rate of fatal police shootings between 2015 and December 2024 stood at 6.1 per million of the population per year, while for white Americans, the rate stood at 2.4 fatal police shootings per million of the population per year. Police brutality in the United States Police brutality is a major issue in the United States, but recently saw a spike in online awareness and protests following the murder of George Floyd, an African American who was killed by a Minneapolis police officer. Just a few months before, Breonna Taylor was fatally shot in her apartment when Louisville police officers forced entry into her apartment. Despite the repeated fatal police shootings across the country, police accountability has not been adequate according to many Americans. A majority of Black Americans thought that police officers were not held accountable for their misconduct, while less than half of White Americans thought the same. Political opinions Not only are there differences in opinion between ethnicities on police brutality, but there are also major differences between political parties. A majority of Democrats in the United States thought that police officers were not held accountable for their misconduct, while a majority of Republicans that they were held accountable. Despite opposing views on police accountability, both Democrats and Republicans agree that police should be required to be trained in nonviolent alternatives to deadly force.