Terror alert system
Terror alert systems are standardised emergency population warning systems for describing and disseminating information about terrorism-related threats. They became more popular after the September 11 attacks on the United States in 2001.
National Counter-Terrorism Alert Level
Administered by the Federal Attorney-General's Department.
Plan Vigipirate
International Terror Threat Level
Administered by the Garda Síochána.
Since November 2015, the international terrorism threat level is considered to be at moderate, meaning an attack is "possible but not likely".
Administered by the Joint Terrorist Analysis Centre
Homeland Security Advisory System
Administered by the Department of Homeland Security
National Terrorism Advisory System
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