The Federal Bureau of Investigation and Department of Homeland Security warned of the threat of a potential lone offender targeting mass gatherings just nine months before a Las Vegas gunman left 59 dead and hundreds more injured on Sunday night.
According to Foreign Policy, the FBI and DHS published the "Joint Special Event Threat Assesssment" in December 2016, which outlined the threat with targets including music venues in Las Vegas. The document obtained by Foreign Policy is unclassified and reveals that last year's New Year’s Eve celebrations along the Las Vegas Strip were of particular concern.
"Unaffiliated lone offenders and [homegrown violent extremists] are of particular concern," so reads the document, "due to their ability to remain undetected until operational; their willingness to attack civilians and soft targets; their ability to inflict significant casualties with weapons that do not require specialized knowledge, access, or training; and their unpredictability, as witnessed in the Orlando, Florida and San Bernardino, California terrorist attacks."
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Before Las Vegas, mass shootings around the world -- including in Orlando at Pule Nightclub -- have repeatedly targetted crowds out at concerts, enjoying nightlife or in open-era venues. The DHS and FBI joint assessment mirrors one often conducted before large U.S. events, and similar breakdowns were recently conducted in lead-up to the Macy's Thanksgiving Day Parade and U.N. General Assembly in New York.
It is important to note that the report, at the time, had "no information to indicate a specific, credible threat to or associated with the America’s Party New Year’s Eve celebration on the Las Vegas Strip and Downtown Las Vegas."
The threat assessment specifically instructed local law enforcement to watch for key behavior indicators, but FP has not made those specific signs public at the request of the FBI.
64-year-old Stephen Paddock fired shots on a Las Vegas country music festival on Sunday from a 32nd-floor window in the Mandalay Bay hotel on Sunday night, before eventually killing himself. The assault lasted several minutes, causing mass panic as thousands fled the scene. Officials are still searching for the gunman's clear motive in perpetrating the deadliest mass shooting in U.S. history.
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