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NTAS Frequently Asked Questions

The following are frequently asked questions regarding the National Terrorism Advisory System.

A – In 2011, the Department of Homeland Security (DHS) replaced the color-coded alerts of the Homeland Security Advisory System (HSAS) with the National Terrorism Advisory System (NTAS), designed to more effectively communicate information about terrorist threats by providing timely, detailed information to the American public.

A – NTAS will now consist 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 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 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.

A – DHS will announce the advisories publicly.  All advisories will be simultaneously posted at DHS.gov, and released to the media for distribution.  DHS will also distribute advisories across its social media channels, including Twitter and Facebook.

A – NTAS advisories – whether they be Alerts or Bulletins – encourage individuals to follow the guidance provided by state and local officials and to report suspicious activity.  Where possible and applicable, NTAS advisories will include steps that individuals and communities can take to protect themselves from the threat as well as help detect or prevent an attack before it happens.  Individuals should review the information contained in the Alert or Bulletin, and based upon the circumstances, take the recommended precautionary or preparedness measures for themselves and their families.

A – NTAS Bulletins will provide broader or more general information about terrorism trends, events, and potential threats in those situations where additional precautions may be warranted, but where the circumstances do not indicate a threat against the United States of sufficient credibility, or specificity and credibility, to issue an Alert.  The NTAS Bulletin will summarize the issue and why it is important for public awareness; outline U.S. Government counterterrorism efforts; and offer recommendations to the public on how it can contribute to the overall counterterrorism effort.

A –Intelligence assessments and risks to the public and critical infrastructure associated with the threat will ultimately drive the decision of whether to issue an NTAS advisory, and whether that advisory will be in the form of a Bulletin or an Alert.  If circumstances and information regarding a specific, credible threat emerges that meet the criteria for an Alert, DHS will issue an Elevated or Imminent Alert to provide warning to the public and affected area or sector.  If the information pertains to a broader or more general trend or development regarding threats to terrorism, DHS may issue a Bulletin.

A – Individuals should report suspicious activity to local law enforcement authorities.  Often, local law enforcement and public safety officials will be best positioned to provide specific details on what indicators to look for and how to report suspicious activity.  The “If You See Something, Say Something®” campaign across the United States encourages the public and leaders of communities to be vigilant for indicators of potential terroristic activity, and to follow the guidance provided by the advisory and/or state and local officials for information about threats in specific places or for identifying specific types of suspicious activity.

A – Americans can go to DHS.gov/alerts to see the most recent advisories. Additionally, advisories will be sent out widely through social and mainstream media.

A – NTAS Bulletins will establish mechanisms and set timelines to regularly re-evaluate the threat or risk identified in the Bulletin.  Because it is based on more specific information, an NTAS Alert will include a “sunset provision” that marks the expected expiration date of the Alert.  Prior to this expiration date, if the threat information or conditions change, the Secretary of Homeland Security may announce an update to the advisory to amend, extend, or rescind it.  All changes, including the announcement that cancels an NTAS advisory, will be distributed the same way as the original Alert or Bulletin.

A – NTAS advisories apply to Americans within the United States and its possessions, but as explained above, NTAS Bulletins may describe general terrorism trends and developments, including trends and developments in other countries, that do not pose a specific threat to the United States.  The Department of State issues security advisory information for U.S. citizens living or traveling in foreign countries.

Last Updated: 12/15/2021
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