Here’s another example, which racked up millions of views in a matter of hours:

“Images that attack the victims of last week’s tragedy in Florida are abhorrent. We are removing this content from Facebook,” Mary deBree, head of content policy at Facebook, told Quartz. However, at the time of publication, when you search “David Hogg” on Facebook, and click on “Articles,” some of the top results are still fake news stories.

On Instagram, another type of fake information proliferated right after the shooting, with users creating fake accounts for the alleged perpetrator, which experts worried might lead to a distorted view of the problem, and affect the way people view potential solutions.  

Motherboard reported that, for some time on Feb. 21, a video claiming Hogg was a crisis actor was the most popular clip on YouTube before the site eventually took it down. The company told Quartz its system had “misclassified” the video because it “contained footage from an authoritative news source.” There are, however, many similar videos still floating around YouTube at the time of publication.

It’s unclear where exactly these posts originate from, but shortly after the shooting, researchers at Hamilton 68, a project that tracks Russian influence online, noticed that Russian-linked Twitter accounts started flooding the internet with hashtags related to the incident, along with politically incendiary content. It was much like how bots operated during the presidential election, aiming to sow division among the American public.

The conspiracy theories from unknown sources are boosted by far-right media personalities, such as Dinesh D’Souza, and Alex Jones and his Infowars website, which latched onto the fact that Hogg is the son of a retired FBI agent, spinning a new thread of the story.

Their influence goes beyond the proverbial pot-stirring uncle sharing a sketchy post on his personal Facebook account. An aide to a state lawmaker in Florida sent a reporter emails claiming the students were actors, with a link to a video to bolster his view. He was later fired. Another tweet pushing the mistruths was liked by Donald Trump Jr.

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