Uncovering and explaining how our digital world is changing — and changing us.

It’s widely known that Facebook, Twitter and YouTube were used by Russian sources during the 2016 U.S. presidential election to try and sway public opinion.

Now we know for certain that Reddit was also part of Russia’s disinformation strategy.

Reddit CEO Steve Huffman posted Monday that the company is in the middle of an “ongoing investigation” into how Russian sources may have used the platform in the run-up to the 2016 election and that Reddit has “removed a few hundred accounts” that were knowingly sharing Russian propaganda.

Huffman also implied that Russian sources did not buy ads on Reddit — “All ads on Reddit are reviewed by humans” — but that “thousands” of users unknowingly shared Russian propaganda that may have first appeared on other sites, like Twitter.

Huffman says that tweets from @TEN_GOP on Twitter, a fake account run by Russians and masquerading as the Republican party of Tennessee, were “amplified by thousands of Reddit users.” That’s from just one Twitter account. There were thousands of Russian-controlled Twitter accounts tweeting Russian propaganda ahead of the election.

“Sadly, from everything we can tell, these [Reddit] users are mostly American, and appear to be unwittingly promoting Russian propaganda,” Huffman wrote. “I believe the biggest risk we face as Americans is our own ability to discern reality from nonsense, and this is a burden we all bear.”

Reddit has been very quiet about its role in the 2016 election despite public concerns from politicians that were voiced as far back as September.

Huffman says that the company is now “cooperating with Congressional inquiries,” though he didn’t say which inquiries or committees he was referring to.

In February, Special Counsel Robert Mueller indicted 13 Russian individuals for using social media to try and support Donald Trump or discredit Hillary Clinton. Reddit was not mentioned in that indictment, but is clearly a part of the bigger story.

We’ve asked Reddit to clarify how many users may have unknowingly shared Russian propaganda in total. We’ve also asked what investigations it is “cooperating” with. We’ll update if we hear back.

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