A rare worldwide travel alert was issued by the U.S. State Department on Monday due to threats posed by the Islamic State group and similar terror networks.
"Current information suggests that ISIL (aka Da’esh) [ISIS], al-Qaida, Boko Haram, and other terrorist groups continue to plan terrorist attacks in multiple regions. These attacks may employ a wide variety of tactics, using conventional and non-conventional weapons and targeting both official and private interests," the alert read. "Authorities believe the likelihood of terror attacks will continue as members of ISIL/Da’esh return from Syria and Iraq. Additionally, there is a continuing threat from unaffiliated persons planning attacks inspired by major terrorist organizations but conducted on an individual basis. Extremists have targeted large sporting events, theaters, open markets, and aviation services."
The alert will affect roughly 50 million Americans traveling for Thursday's Thanksgiving holiday.
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"U.S. citizens should exercise vigilance when in public places or using transportation. Be aware of immediate surroundings and avoid large crowds or crowded places. Exercise particular caution during the holiday season and at holiday festivals or events," the alert read, USA Today reported.
The State Department usually issues alerts for specific countries, but it is uncommon to issue a blanket alert for all travel.
The decision comes just two weeks after the Paris, France, terror attacks killed 129, along with an ABC News interview the same day where President Obama said ISIS was "contained."
"I don't think they're gaining strength. From the start, our goal has been first to contain, and we have contained them. They have not gained ground in Iraq," Obama told the network for a Nov. 13 interview.
An ISIS propaganda video released Nov. 18 included images of Times Square and Herald Square in New York City as targets for terror.
"What's coming next will be far worse and more bitter," the tape said, the New York Post reported.
The State Department alert expires on Feb. 24, 2016.