The law enforcement sensitive bulletin was issued following a series of online threats made in relation to the film debuting this weekend. .

The US Army has also warned service members about the possibility of mass shootings at screenings of the movie. The cautionary statement urged individuals to be aware of their surroundings, as well as to “identify two escape routes” for potential use in the event of a shooting.

Both bulletins explain that "incels," a term referring to an online subculture of men who are involuntarily celibate and blame their situation on women, sometimes idolize the Joker character who himself is marginalized by society and ultimately turns to violence.