The National Terrorism Advisory System (NTAS) is designed to communicate information about terrorist threats by providing timely, detailed information to the American public. All Americans share responsibility for the nation's security, and should always be aware of the heightened risk of terrorist attack in the United States and what they should do.
DHS replaced the color-coded alerts of the Homeland Security Advisory System (HSAS) with the National Terrorism Advisory System (NTAS) in 2011.
This page contains current NTAS advisories (both Alerts and Bulletins), archived copies of expired advisories, and additional information on the NTAS system.
https://www.dhs.gov/national-terrorism-advisory-system
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