Terrorism
Protecting the United States from terrorist attacks is the FBI’s number one priority. The Bureau works closely with its partners to neutralize terrorist cells and operatives here in the United States, to help dismantle extremist networks worldwide, and to cut off financing and other forms of support provided to foreign terrorist organizations.

Terrorism Definitions
International terrorism: Violent, criminal acts committed by individuals and/or groups who are inspired by, or associated with, designated foreign terrorist organizations or nations (state-sponsored).
Domestic terrorism: Violent, criminal acts committed by individuals and/or groups to further ideological goals stemming from domestic influences, such as those of a political, religious, social, racial, or environmental nature.
- Reports: Strategic Intelligence Assessment and Data on Domestic Terrorism
The Current Threat
The FBI is committed to remaining agile in its approach to the terrorism threat, which has continued to evolve since the September 11, 2001 terror attacks. Years after these attacks, the threat landscape has expanded considerably, and international terrorism remains a serious threat. The threat of domestic terrorism also remains persistent overall, with actors crossing the line from exercising First Amendment-protected rights to committing crimes in furtherance of violent agendas.
Many factors have contributed to the evolution of the terrorism threat on both the international and domestic fronts, such as:
- Lone offenders: Terrorist threats have evolved from large-group conspiracies toward lone-offender attacks. These individuals often radicalize online and mobilize to violence quickly. Without a clear group affiliation or guidance, lone offenders are challenging to identify, investigate, and disrupt. The FBI relies on partnerships and tips from the public to identify and thwart these attacks.
- The internet and social media: International and domestic violent extremists have developed an extensive presence on the Internet through messaging platforms and online images, videos, and publications. These facilitate the groups’ ability to radicalize and recruit individuals who are receptive to extremist messaging.
Social media has also allowed both international and domestic terrorists to gain unprecedented, virtual access to people living in the United States in an effort to enable homeland attacks. The Islamic State of Iraq and ash-Sham (ISIS), in particular, encourages sympathizers to carry out simple attacks wherever they are located—or to travel to ISIS-held territory in Iraq and Syria and join its ranks as foreign fighters. This message has resonated with supporters in the United States and abroad.
Terrorism Investigations
The FBI is bound by guidelines issued by the attorney general that establish a consistent policy on when an investigation may be initiated. Through these guidelines, the FBI obtains authorization to collect information. The facts are analyzed and then used to prevent terrorist activity and, whenever possible, to aid in the arrest and prosecution of persons or groups who have violated the law.
The approach taken by the FBI in counterterrorism investigations is based on the need both to prevent incidents where possible and to react effectively after incidents occur. Our investigations focus on the unlawful activity of the group, not the ideological orientation of its members. When conducting investigations, the FBI collects information that not only serves as the basis for prosecution but also builds an intelligence base to help prevent terrorist acts.
How Citizens Can Protect Themselves and Report Suspicious Activity
It is important for people to protect themselves both online and in-person, and to report any suspicious activity they encounter. The simplest ways to accomplish this are to:
- Remain aware of your surroundings.
- Refrain from oversharing personal information.
- Say something if you see something. The insular nature of today’s violent extremists makes them difficult for law enforcement to identify and disrupt before an attack. Many times, a person’s family or friends may be the first to notice a concerning change in behavior that may indicate a person is mobilizing to violence.
Additional information regarding how to report suspicious activity and protect the community is available via the resources below.
- Nationwide SAR Initiative (NSI): The Nationwide Suspicious Activity Reporting (SAR) Initiative is a joint collaborative effort by the U.S. Department of Homeland Security, the FBI, and law enforcement partners.
- Community Preparedness Tools: The Department of Homeland Security offers security resources for businesses and communities.
- The Contact Us section of fbi.gov provides detailed contact information for the FBI’s local and international offices. You can also submit a tip online.
- The U.S. Violent Extremist Mobilization Indicators booklet lists behaviors that could mean someone is planning ideologically motivated violence.
- Five Eyes Insights: Young people and violent extremism: a call for collective action: Five Eyes law enforcement and security agencies are calling for a whole-of-society response to help identify and deal with the radicalization of minors—especially online—across the Five Eyes nations.
Asset Forfeiture
Asset forfeiture is a powerful tool used by law enforcement agencies, including the FBI, against criminals and criminal organizations to deprive them of their property used illegally and their ill-gotten gains through seizure of these assets. It is also used to compensate victims of crime. Learn more about the FBI’s asset forfeiture program and to see forfeiture in action.
Partnerships
Combating terrorism effectively requires the continuous exchange of information and close, daily coordination among U.S. law enforcement, members of the U.S. Intelligence Community, first responders, international law enforcement agencies, and others. To help ensure the two-way flow of information and intelligence, the FBI participates in numerous national and local joint terrorism task forces and interagency initiatives such as the National Counterterrorism Center and in fusion centers.
- 02.11.2025 — Durham Man Pleads Guilty to Conspiring to Provide Support to Terrorists
- 02.11.2025 — California Teenager Sentenced to 48 Months in Prison for Nationwide Swatting Spree
- 02.07.2025 — Defendant Sentenced to 15 Years in Prison for Soliciting a Minor and Lying to the FBI About Pro-ISIS Social Media Postings
- 02.07.2025 — Bristol Man Who Made Interstate Threats is Sentenced
- 02.04.2025 — Member of Al Qaeda in the Arabian Peninsula Sentenced to 44 Years in Prison for Terrorism Offenses
- 02.03.2025 — White Supremacist Leader Found Guilty of Conspiring to Destroy Regional Power Grid
- 01.27.2025 — New Jersey Man Pleads Guilty to Attempting to Provide Material Support to al Shabaab
- 01.23.2025 — Two Tucson Men Sentenced for Conspiring to Travel to the Middle East to Fight for ISIS