The landscape of terrorism has evolved significantly in recent years. One significant development is the U.S. government’s historic decision to designate certain gangs and cartels in Latin America as terrorist groups, reflecting a broader understanding of what constitutes terrorism. Meanwhile, acts of violence committed by individuals have consistently been a major concern within the United States and Europe, and continue unabated. For instance, a recent attack in Washington on November 26, where an Afghan immigrant critically injured two National Guard members, underscores the growing threat from lone actors. Only weeks earlier, on 2 October, during Yom Kippur, a lone attacker targeted a synagogue in Manchester, resulting in the death of one worshipper and the accidental fatal shooting of another by police. Such incidents in 2025—carried out by self-radicalized attackers targeting political sites, religious institutions, and public events—further highlight the increasing significance of politically motivated and individually executed violence.
Traditionally, terrorist perpetrators have included individuals, groups, organizations, and even states. However, lone-actor attackers have gained increased scholarly and policy attention because of their unpredictability, difficulty to detect, and potential to cause significant harm. Although global terrorist activity remains high—around 7,000 to 10,000 attacks annually over the past seven years, according to the GTTAC database—lone-actor incidents make up only a few hundred cases each year. This article examines lone-actor attacks from 2010 to 2024 using a dataset created by the authors from open sources, identifies common individual- and incident-level traits, and explores any geographic or temporal patterns.
Despite ongoing academic and policy attention on major jihadist groups, lone actors continue to appear unexpectedly, targeting both civilians, security personnel, and various governmental and non-governmental institutions. To better understand this trend, the authors assembled a detailed dataset on lone-actor terrorism, examining offender profiles, ideological motives, regional and temporal patterns, and attack severity across various ideological categories. The dataset includes incidents from 2010 to 2024, with data collection for 2025 still in progress to stay current. The year 2010 is used as the starting point because, by then, lone-actor terrorism had become one of the most urgent and dangerous types of terrorist violence.
Data were gathered from reputable open-access media sources and independently coded by two coders using a global open-source reporting framework. For this article, the analysis focuses on incidents recorded from 2010 to 2024, covering 923 attacks across 64 countries and 562 cities. The dataset’s geographic distribution is approximately 50% in Israel–Palestine, 20.9% in Europe, and 18% in North America. After data collection, the authors calculated a weighted severity score that assigns much greater importance to fatalities than to non-fatal injuries, reflecting their larger strategic and societal impact while still accounting for non-lethal harm. For example, under this system, about 20 wounded individuals caused by a lone actor attack have a severity value similar to one fatality. This measure offers a standardized way to compare incident severity across countries, years, and ideological motives, and it serves as the dependent variable in several statistical analyses within the study.
The database includes only violent assailants who carry out attacks motivated by identifiable terrorist ideologies—such as jihadism, right-wing extremism, or left-wing terrorism—and who operate without receiving orders from or maintaining formal ties to any designated terrorist organization or hierarchy. In this study, lone-actor terrorists are defined as individuals who plan and execute violent acts independently, follow their own schedule, and pursue ideologically driven goals aimed at intimidating, coercing, or influencing civilians or governments. This distinguishes lone-actor terrorism from related phenomena like hate crimes and mass shootings. Hate crimes are criminal acts against persons or property motivated wholly or partly by bias against federally protected groups (e.g., race, religion, ethnicity, disability, or sexual orientation), with the goal of harming targeted individuals and intimidating the wider protected community. While terrorism can overlap with hate crimes when attacks target protected groups, not all hate crimes are considered terrorism, as they may lack the broader coercive or political motives characteristic of terrorist acts. Mass shootings are usually defined as incidents involving the killing of four or more people in a single event without a “cooling-off” period; they often occur without a clear ideological motive and may be linked to personal grievances or mental health issues. In this research, incidents lacking an identifiable ideological intent are excluded. Therefore, the database focuses solely on attacks where evidence—such as statements, writings, or social media posts—indicates that the perpetrator was motivated by a terrorist ideology and acted alone.
The dataset highlights several key traits of lone-actor perpetrators, including age, gender, occupation, prison history, and the place of radicalization. Age data is available for 417 incidents, showing that the attackers ranged from 13 to 84 years old, with an average age of 30.25 and a median age of 27; notably, 75 percent of perpetrators were 36 or younger. No significant link was found between attacker age and casualty numbers. Gender data reveal that lone-actor terrorism is predominantly male, with 93.7 percent of perpetrators identified as men (n = 622). Information on prison history is more limited (n = 106), yet among these, 70 individuals had prior incarceration, indicating that a sizable portion of lone actors have had contact with the criminal justice system. This pattern aligns with findings from Western Europe, where researchers have identified “hybrids”—individuals who shift from criminal activity to violent extremism, often radicalized during periods of imprisonment.
The dataset classifies lone-actor attacks based on the perpetrators’ ideological motivations. Western-born Muslim individuals inspired by jihadist ideologies—usually self-radicalized through online platforms and social media—are categorized as jihadist attackers. Incidents in Israel and Palestine are labeled as ethnonationalist, reflecting long-standing patterns of violence where both civilians and military personnel are targeted through individually initiated attacks. Left-wing extremist incidents include those motivated by Marxist or communist beliefs, while single-issue extremists are driven by causes such as environmentalism, animal rights, anti-abortion activism, or misogynistic incel ideologies. The ideological breakdown in Figure 1 shows that ethnonationalist attacks account for 405 incidents (45.0 percent), followed by 247 jihadist attacks (27.5 percent), and 154 right-wing extremist attacks (17.1 percent). Left-wing extremist incidents include 22 cases (2.4 percent), single-issue cases number 7 (0.8 percent), and 46 incidents (5.1 percent) are categorized as “other,” with 18 incidents (2.0 percent) remaining ideologically unclassified.
The database summarizes the severity and outcomes of 923 lone-actor incidents. The overall fatality rate (0.2784) indicates that just over one-quarter of incidents resulted in at least one death, while the injury rate (0.532) shows that injuries occurred in about half of all cases. On average, incidents caused 1.018 deaths and 4.402 injuries, emphasizing that non-fatal harm was much more common than lethal outcomes.
Figure 2 below shows temporal patterns in lone-actor terrorism by casualty type from 2010 to 2024, comparing global data (left panel) with data excluding the Israel–Palestine region (right panel). When all regions are included, incident numbers rise sharply after 2015, peak around 2018, and increase again in 2024. A similar, though less pronounced, trend appears when Israel–Palestine is excluded, indicating that while this region significantly affects global spikes, it doesn’t fundamentally change the overall temporal pattern.
Across both panels, non-fatal incidents—those resulting only in injuries or no casualties—consistently outnumber fatal incidents. However, incidents involving both fatalities and injuries show a notable increase after 2016. These patterns suggest that while lone-actor terrorism has become more common over the past decade, most incidents do not lead to deaths, reflecting a shift toward more frequent but lower-fatality events.
The right panel, which excludes incidents from Israel–Palestine, shows reduced intensity and lower volatility while maintaining similar overall patterns: growth from 2017 to 2019, a decline in 2020–2021, and a partial rebound afterward. This indicates that although Israel–Palestine contributes to global peaks, it does not drive broader international trends. Overall, the data point to occasional increases in lone-actor activity and a recent uptick in incidents—contradicting expectations of post-2018 normalization—and suggest that emerging factors like online radicalization, political polarization, and pandemic-related social disruptions are keeping baseline levels elevated.
An analysis of incident outcomes in Figure 3 shows consistent patterns in the outcomes for lone-actor perpetrators. In all documented cases, attackers were killed in 34.6 percent of incidents, captured in 31.8 percent, escaped in 20.7 percent, wounded in 10.8 percent, and died by suicide in 2.1 percent of cases. These numbers suggest that about 80 percent of lone-actor terrorists are either killed or captured during or right after the attack. Additionally, Figure 3 demonstrates that the chance of an attacker being killed increases with the severity of the incident, highlighting a strong link between high-impact attacks and the higher risk of the perpetrator dying.
When these outcome variables are analyzed across regions in Figure 4, distinct geographic patterns become evident. The highest proportions of attacker fatalities, injuries, and escapes are observed in the Israel–Palestine region, reflecting the increased security concerns and higher risks associated with confrontations in this area. Conversely, the highest rates of perpetrator capture are found in North America, followed by Europe, indicating a stronger reliance on law enforcement and a greater chance of apprehending attackers alive in these regions.
An analysis of target selection in lone-actor incidents shows a consistent focus on certain categories despite overall variation. Security forces account for the largest share of attacks (40 percent), followed by civilians (33.3 percent). Additionally, 11.7 percent of incidents target religious individuals or places of worship, which are also considered civilian targets.
Figure 5 shows how the ten most targeted categories changed from 2010 to 2024. Incident numbers were low in the beginning, rose steadily after 2014, and then surged between 2017 and 2019. There was a drop in 2022, followed by a sharp rebound to the highest level in 2024. This increase is mainly driven by attacks on security forces and civilians, which consistently make up most of the targets across nearly all years. Smaller but ongoing contributions come from political figures, Jewish and Muslim civilians, with occasional spikes involving the justice system and government buildings. Diplomats remain rarely targeted. Overall, the data reveal a uneven but clear growth in lone-actor attacks over the decade, with recent years showing more activity and a target profile mainly focused on security personnel and civilians.
A closer look at casualty distribution in Figure 6 highlights the disproportionate effect of lone-actor attacks on civilians. As shown in the second graph, civilians make up the vast majority of casualties, with 575 killed and 3,189 injured. Security forces are the second most affected group, with 111 fatalities and 446 injuries, though at much lower levels. Other target groups—including religious sites (temples, mosques, and Jewish civilians), political figures, Christian civilians, and government buildings—show comparatively smaller casualty counts, usually under 100 in total. This pattern indicates that lone-actor attacks mainly impact civilian populations, implying that these incidents often aim to cause indiscriminate or symbolic harm rather than targeting state or military personnel.
An analysis of weapon types in lone-actor attacks shown in Figure 7 highlights a clear distinction between frequency and severity. Melee or knife attacks are by far the most common, followed by pistols, explosives or IEDs, vehicles, and rifles. However, many knife and pistol incidents result in no casualties or only minor injuries, as shown by the high occurrence of low-severity outcomes in the data. In contrast, incidents involving rifles, explosives, and vehicles, though less frequent, are more likely to cause fatalities or a mix of deaths and injuries, emphasizing their greater lethality.
Ideological orientation significantly influences weapon and tactic choices in lone-actor attacks. Melee or knife assaults are most common among various ideological groups, especially among ethnonationalist and jihadist actors, as shown in Figure 8. Pistols and rifles are also used frequently, particularly by ethnonationalist offenders, while explosives/IEDs and vehicles occur across different ideologies but less often. Right-wing extremists tend to use a diverse range of weapons evenly, suggesting a more adaptable and opportunistic strategy rather than dependence on a single method.
Tactical patterns also reflect ideological influences. Stabbing is the most common tactic overall, especially among jihadist and ethnonationalist actors, followed by shooting, which is mainly linked to ethnonationalist incidents. Vehicle ramming is more common among right-wing extremists, while bombing tactics are mainly used by jihadist perpetrators. Less common tactics—including arson, sabotage or vandalism, and threats or intimidation—generally correspond to lower-capacity operations or symbolic attacks.
These patterns show that ideology greatly influences weapon and tactic choices, but situational opportunity and resource availability are still crucial factors. Jihadist and ethnonationalist lone actors usually rely on close-contact or traditional weapons, while right-wing extremists use a wider range of tactics, reflecting decentralized planning and adaptable violence.
The dataset confirms that lone-actor incidents are highly diverse in both method and impact, making it difficult to define a single typology. Weapon choice is a strong predictor of lethality: rifles, explosives, and vehicles tend to cause more severe outcomes, while knives and pistols are more common but usually result in fewer casualties. Civilians are the most targeted group across ideological categories, highlighting the mostly indiscriminate and symbolic nature of these attacks. Ideological motivations affect tactical choices but do not necessarily determine lethality—both right-wing and jihadist actors can carry out high-impact operations. Patterns over time show ongoing or renewed lone-actor activity after 2015, mainly driven by accessible tactics rather than formal command structures.
Several policy implications emerge from this analysis. First, counterterrorism strategies should focus on early detection and intervention for high-risk individuals, especially online, where radicalization—whether jihadist or right-wing—is becoming more common. The rise of right-wing governments and the spread of extremist ideologies in Western societies may create a social and political environment that encourages lone-actor mobilization. Similarly, online jihadist platforms continue to offer technical guidance, ideological reinforcement, and encouragement, maintaining the threat from self-radicalized individuals. Second, security measures should target the weapon–lethality relationship identified in the data; high-risk weapons like rifles, explosives, and vehicles need specific prevention and control efforts. Third, the high rate of civilian casualties highlights the need for broader public safety initiatives, such as emergency preparedness, threat awareness campaigns, and quick response procedures. Finally, major geopolitical events like the Hamas attacks of October 7, 2023, can trigger radicalization and copycat acts, underscoring the importance of monitoring the wider socio-political environment to anticipate potential increases in lone-actor activity. In summary, reducing the threat of lone-actor terrorism requires a comprehensive approach that combines targeted law enforcement, public education, online radicalization monitoring, and analysis of the larger ideological and geopolitical context in which these attacks happen.