(CNN) @tpartynews looked as American as could be. A Twitter account, its profile photo on the site was a "Tea Party" teapot in the colors of the American flag. Its cover photo was an image of the U.S. Constitution.

In the lead-up to the 2016 presidential election, @tpartynews posted pro-Trump, conservative and anti-immigrant messages. It regularly retweeted Fox News, Ann Coulter and other conservative Twitter accounts. And 22,000 accounts followed it -- one of them former White House advisor Sebastian Gorka's.

But @tpartynews wasn't American. It was part of a Russian propaganda operation, according to Russian journalists who discovered the link.

Those journalists discovered that @tpartynews was linked to Russia's Internet Research Agency, a shadowy news service with ties to the Kremlin -- one of up to 50 such twitter accounts which collectively had more than 600,000 followers. The Internet Research Agency was also the group linked to $100,000 worth of politically-themed ads purchased on Facebook during the 2016 election, the existence of which Facebook disclosed to Congress and the public earlier this month.

As with Facebook, there is growing evidence that foreign governments, including Russia, used Twitter to try and influence public opinion during the 2016 U.S. election.

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