Forty-seven minutes after news broke of a high school shooting in Parkland, Fla., the posters on the anonymous chat board 8chan had devised a plan to bend the public narrative to their own designs: “Start looking for [Jewish] numerology and crisis actors.”

The voices from this dark corner of the Internet quickly coalesced around a plan of attack: Use details gleaned from news reports and other sources to push false information about one of America’s deadliest school shootings.
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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.

The Parkland story line took advantage of emerging details about the surviving students — and even how they looked or talked during interviews with television reporters — to portray them as “crisis actors” playing the roles of victims in a “false flag” attack, a hoax designed to mislead the public and build support for gun control. —We studied thousands of anonymous posts about the Parkland attack — and found a conspiracy in the making (Washington Post)