Russia had a hand in spreading fake news to millions of Americans during the election cycle, according to two independent research groups, PropOrNot and Foreign Policy Research Institute.

The Washington Post was the first media outlet to report PropOrNot’s findings that there are over 200 websites described as “routine peddlers of Russian propaganda during the election season, with combined audiences of at least 15 million Americans.” The most recognizable names on the list of “sites that reliably echo Russian propaganda” include Alex Jones’ Infowars, Julian Assange’s Wikileaks and Matt Drudge’s Drudge Report. Others include The Federalist Papers, ZeroHedge, the Free Thought Project and USAPoliticsNow.

PropOrNot wrote, “Please note that our criteria are behavioral. That means the characteristics of the propaganda outlets we identify are motivation-agnostic. For purposes of this definition it does not matter whether the sites listed here are being knowingly directed and paid by Russian intelligence officers, or whether they even knew they were echoing Russian propaganda at any particular point: If they meet these criteria, they are at the very least acting as bona-fide ‘useful idiots‘ of the Russian intelligence services, and are worthy of further scrutiny.”

Also Read: Fake News Writer Finally Realizes Americans Take Fake News Seriously: 'It's Scary'

Jones, Drudge and Assange did not immediately respond to TheWrap’s request for comment.

PropOrNot, which launched this year “as an effort to prevent propaganda from distorting U.S. political and policy discussions,” describes itself as “an independent team of concerned American citizens with a wide range of backgrounds and expertise, including professional experience in computer science, statistics, public policy, and national security affairs.”

The organization estimated that false stories either planted or promoted by Russia’s sophisticated disinformation campaign were viewed more than 213 million times on Facebook.

Also Read: Sean Hannity Rips Basically Every Outlet Other Than Fox as 'Fake News'

One such story, debunked by The Daily Beast, was a WikiLeaks claim about Hillary Clinton’s health in wake of being treated for pneumonia after looking ill at a Sept. 11 memorial event in New York. While the Daily Beast’s explanation of Clinton’s “decision fatigue” — a term WikiLeaks uncovered in a Clinton email and interpreted as an illness (it’s not) — reached 1,700 Facebook accounts and was read online more than 30,000 times, a version of the story spread by Russian propaganda reached 90,000 Facebook accounts and was read more than 8 million times.

“They want to essentially erode faith in the U.S. government or U.S. government interests,” Clint Watts, a researcher for the Foreign Policy Research Institute, told The Washington Post. “This was their standard mode during the Cold War. The problem is that this was hard to do before social media.”

Also Read: CBS' Scott Pelley Calls Fake News 'The Quickest, Most Direct Way to Ruin a Democracy' (Video)

Watts’ research was published earlier this month under the headline “Trolling for Trump: How Russia Is Trying to Destroy Our Democracy” on War on the Rocks, an online platform for analysis, commentary, debate and multimedia content on foreign policy and national security issues.

Watts, along with co-authors Andrew Weisburd and J.M. Berger, argued before election day that while Russia’s propaganda effort may benefit the Trump campaign, “the ultimate objective is to diminish and tarnish American democracy.”

The strategy relies on a complicated mix of elements that contribute to the spread of disinformation through social media trolling, conspiracy theory websites (Infowars), parody news sites, data dumps (WikiLeaks) and news aggregators (Drudge Report). Watts and company explain:

“A small army of social media operatives — a mix of Russian-controlled accounts, useful idiots, and innocent bystanders — are deployed to promote all of this material to unknowing audiences. Some of these are real people, others are bots, and some present themselves as innocent news aggregators, providing ‘breaking news alerts’ to happenings worldwide or in specific cities. The latter group is a key tool for moving misinformation and disinformation from primarily Russian-influenced circles into the general social media population. We saw this phenomenon at play in recent reports of a second military coup in Turkey and unsubstantiated reports of an active shooter that led to the shutdown of JFK Airport. Some news aggregators may be directly controlled by Russia, while other aggregators that use algorithmic collection may be the victims of manipulation.”

Russia, however, has repeatedly denied any such manipulation, along with Kremlin propaganda outlet RT, formerly called Russia Today, which told the Washington Post on Friday it “adamantly rejects these claims” of producing or helping to spread fake news stories during the U.S. election.

PropOrNot launched the YYYcampaignYYY Friday, asking others to help identify Russian propaganda circulating online by manually marking suspicious headlines, social media accounts or websites with YYY on both sides while pushing back against the person who posted “as kindly as possible.” The organization has even created a Google Chrome plugin that will highlight links to alleged Russian propaganda sites while browsing.