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  4. National Terrorism Advisory System Bulletin - May 15, 2017

National Terrorism Advisory System Bulletin - May 15, 2017

A blue banner displaying the U.S. Department of Homeland Security seal with the text National Terrorism Advisory System - Bulletin - www.dhs.gov/advisories
A blue banner displaying the U.S. Department of Homeland Security seal with the text National Terrorism Advisory System - Bulletin - www.dhs.gov/advisories

National Terrorism Advisory System Bulletin

Date Issued: May 15, 2017 11:30 PM ET
View as PDF:  National Terrorism Advisory System Bulletin - May 15, 2017 11:30 pm (pdf, 1 pages, 608.02 KB)

Summary of Homegrown Terrorism Threat

Since 2015, the Department of Homeland Security (DHS) has used this Bulletin to highlight the continuing threat from homegrown terrorists, many of whom are inspired online to violence by foreign terrorist organizations. The United States is engaged in a generational fight against terrorists, who seek to attack the American people, our country, and our way of life. An informed, vigilant, and engaged public remains one of our greatest assets to identify potential homegrown terrorists and prevent attacks.


Issued:   May 15, 2017 11:30 PM ET
Expires:   November 09, 2017 12:00 AM ET

Additional Details

  • We face one of the most serious terror threat environments since the 9/11 attacks as foreign terrorist organizations continue to exploit the Internet to inspire, enable, or direct individuals already here in the homeland to commit terrorist acts.
  • Homegrown terror suspects are increasingly relying on technology, such as end-to-end encrypted social media applications, to avoid detection.  Moreover, terrorist groups are urging recruits to adopt easy-to-use tools to target public places and events. Specific attack tactics have included the use of vehicle ramming, small arms, straight-edged blades or knives, and homemade explosives, as well as other acts such as taking hostages.
  • As the United States steps up efforts to disrupt and defeat terrorist groups overseas, we will continue to face a multi-faceted threat environment.
  • Specifically, continued successes aimed at disrupting and defeating terrorist groups overseas may encourage homegrown terrorists inside the United States to carry out acts of violence.
  • Additionally, foreign terrorist fighters, who have acquired training and battle-tested terrorism experience, are likely to flee from terrorist-controlled territories with a desire to conduct attacks elsewhere, including the United States. Some of these individuals may be U.S. citizens or citizens of other nations attempting to travel to the United States on visas, from visa-waiver countries, with the aim of attacking the homeland or inciting others within our borders to conduct attacks.

U.S. Domestic Counterterrorism Efforts

  • DHS and the FBI continue to provide guidance to state, local, tribal and territorial partners related to the current threat environment. DHS also partners closely with the private sector to provide risk assessments and coordinate security measures with business owners and operators. The public may continue to observe law enforcement and security activity in and around public places and events.
  • DHS is taking steps to address the threat from foreign terrorist fighters who have traveled or attempt to travel to the United States, including working closely with the FBI and Intelligence partners to identify U.S. persons who left the country to join terrorist groups, as well as putting in place enhanced screening and vetting measures to detect travelers with potential terrorist connections.
  • More broadly, we remain committed to preventing violence and threats meant to intimidate or coerce specific populations on the basis of their religion, ethnicity, or identity, and we will seek justice against the perpetrators of such acts.

Types of Advisories


Describes current developments or general trends regarding threats of terrorism.

Elevated Alert

Warns of a credible terrorism threat against the United States.

Imminent Alert

Warns of a credible, specific and impending terrorism threat against the United States.

How You Can Help

  • Report suspicious activity to local law enforcement who are best to offer specific details on terroristic indicators.
  • Suspicious activity or information about a threat may also be reported to Fusion Centers and the FBI’s Field Offices - part of the Nationwide Suspicious Activity Reporting Initiative. DHS and FBI are especially interested in unusual foreign travel to known terrorist locations.
  • Learn how to recognize signs of pre-operational planning associated with terrorism or other criminal activity.

Be Prepared

  • Be prepared for security and plan ahead. Anticipate delays and restrictions on items around populated places and at events.
  • Be responsible for your personal safety. Make a mental note of emergency exits and security personnel. Carry emergency contact and special needs info with you at all times.
  • Business owners are encouraged to Connect, Plan, Train, and Report to prepare businesses & employees. Security tools/resources can be accessed through the DHS’s Hometown Security Campaign.
  • For more visit Ready.

Stay Informed

  • The U.S. Government will provide additional information about any emerging threat as additional information is identified. The public is encouraged to listen to local law enforcement and public safety officials.
  • We urge Americans to continue to travel, attend public events, and freely associate with others but remain vigilant and aware of surroundings.
  • The Department of State issues international travel alerts and warnings.
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