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  3. Preventing Terrorism and Targeted Violence
  4. National Terrorism Advisory System

National Terrorism Advisory System

National Terrorism Advisory System (NTAS) advisories communicate information about terrorist threats by providing timely, detailed information to the public, government agencies, first responders, public sector organizations, airports and other transportation hubs.

Using available information, the advisories will provide a concise summary of the potential threat, information about actions being taken to ensure public safety, and recommended steps that individuals, communities, businesses and governments can take to help prevent, mitigate or respond to the threat.

Bulletins and Alerts

NTAS consists of two types of advisories: Bulletins and Alerts.  DHS has added Bulletins to the advisory system to be able to communicate current developments or general trends regarding threats of terrorism.  NTAS Bulletins permit the Secretary of Homeland Security to communicate critical terrorism information that, while not necessarily indicative of a specific threat against the United States, can reach homeland security partners or the public quickly, thereby allowing recipients to implement necessary protective measures.  Because DHS may issue NTAS Bulletins in circumstances not warranting a more specific warning, NTAS Bulletins provide the Secretary of Homeland Security with greater flexibility to provide timely information to stakeholders and members of the public.

As before, when there is specific, credible information about a terrorist threat against the United States, DHS will share an NTAS Alert with the American public when circumstances warrant doing so.  The Alert may include specific information, if available, about the nature of the threat, including the geographic region, mode of transportation, or critical infrastructure potentially affected by the threat, as well as steps that individuals and communities can take to protect themselves and help prevent, mitigate or respond to the threat.  The Alert may take one of two forms: Elevated, if we have credible threat information, but only general information about timing and target such that it is reasonable to recommend implementation of protective measures to thwart or mitigate against an attack, or Imminent, if we believe the threat is credible, specific, and impending in the very near term.

Hear About Advisories Through our Website or Social Media Channels

NTAS is built on a clear and simple premise: When a threat develops that could impact you – the public – we will tell you. We will provide whatever information we can so you know how to protect yourselves, your families, and your communities.

For Americans, this will mean some visible changes. You won’t hear the old color-code announcements when you go to airports, or see them when you visit a government website. Instead, when a threat arises that could affect you and your family, you will hear about it through an NTAS advisory issued by DHS through official channels, such as the National Terrorism Advisory System page, the news media, and via social media channels such as Facebook and Twitter.

Other Types of Advisories

Travel alerts and warnings are maintained by the U.S. Department of State and are a resource for international travelers to consider for safe travel overseas. Learn more about travel alerts here.

Additional Information


Last Updated: 11/01/2022