The U.S. government has urged service members to take extra precaution at screenings of Todd Phillips' Joker

According to a Sept. 18 email obtained by Gizmodo, the warning stems from an FBI bulletin about recent online activity involving "incel" extremists who "idolize the Joker character." The email echoed concerns about potential violence inspired by the deadly 2012 Aurora theater shooting, which occurred during a screening of the Dark Knight Rises.

"Posts on social media have made reference to involuntary celibate ('incel') extremists replicating the 2012 theater shooting in Aurora, Colorado, at screenings of the Joker movie at nationwide theaters," the email read. "... When entering theaters, identify two escape routes, remain aware of your surroundings, and remember the phrase 'run, hide, fight.' Run if you can. If you’re stuck, hide (also referred to as 'sheltering in place'), and stay quiet. If a shooter finds you, fight with whatever you can."

A spokesperson for the U.S. Army told Gizmodo that the email was sent as a precautionary measure, and that officials were not aware of any specific attack plots.

"We do this routinely because the safety and security of our workforce is paramount," the representative told the outlet. "We want our workforce to be prepared and diligent on personal safety both inside the workplace and out."

You can read the military email below. Joker, starring Joaquin Phoenix, will hit U.S. theaters on Oct. 4

Team,

Posts on social media have made reference to involuntary celibate ("incel") extremists replicating the 2012 theater shooting in Aurora, Colorado, at screenings of the Joker movie at nationwide theaters. This presents a potential risk to DOD personnel and family members, though there are no known specific credible threats to the opening of the Joker on 4 October.

Incels are individuals who express frustration from perceived disadvantages to starting intimate relationships. Incel extremists idolize violent individuals like the Aurora movie theater shooter. They also idolize the Joker character, the violent clown from the Batman series, admiring his depiction as a man who must pretend to be happy, but eventually fights back against his bullies.

When entering theaters, identify two escape routes, remain aware of your surroundings, and remember the phrase “run, hide, fight.” Run if you can. If you’re stuck, hide (also referred to as “sheltering in place”), and stay quiet. If a shooter finds you, fight with whatever you can.

** this is a condensed version of an HQ Army Materiel Command, G-3, Protection Division Security message **

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