During the week of November 16th, the pro-IS group Wafa Media Foundation released a propaganda poster depicting a jihadist armed with a rifle driving into St. Peter's Basilica in Rome with a written message warning of a Christmas attack.
SITE Intelligence Group, a Maryland-based company devoted to tracking online activities of extremist organizations, drew the media's attention to the poster and suggested that it was meant to encourage so-called "lone wolf" attacks. Source: Newsweek
Link to view the poster: Site Intelligence Group