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“There’s a war going on outside, no man is safe from,” said a frequent conspiracy theory poster on the website Reddit, the day after the shooting. “And it is only partially being fought with guns. The real weapon is information and the attack is on the mind.”
A Washington Post review of thousands of posts on sites such as 8chan, 4chan and Reddit showed how people on online forums worked aggressively to undermine news reports about a troubled teen accused of killing 17 people, most of them students.
Former YouTube engineer Guillaume Chaslot referred to coordinated campaigns across online platforms to spread a video as “4chan attacks” because such anonymous forums often served as staging grounds for these efforts. YouTube and Facebook have policies against harassment that served as the basis for removing some of the conspiracy theories. But Chaslot said the companies have not done enough to weed out deceptive content.