There could be an unlikely winner in this weekend's efforts to hold an independence referendum in Catalonia: Russia.

In recent weeks, Russian state-backed news organizations and automated social network accounts, known as bots, have aggressively promoted digital misinformation and outright fake news about the politically charged vote planned for Sunday, according to an analysis of recent online activity.

The efforts — aimed at discrediting Spanish political and legal authorities that are trying to clamp down on the Catalan government's attempt to hold the outlawed referendum — follows similar digital misinformation campaigns during Europe's season of elections in 2017.

These online activities are intended to cast doubt over Europe's democratic processes at a time of heightened tensions between the EU and Russia, experts warn.

From the French and German elections to votes coming soon in Spain and the Czech Republic, among others, Russian-backed online networks have routinely championed extremist groups through social media and digital news outlets.

“Spain’s government acts like a banana monarchy — embarrassing for Europe!” — Julian Assange, founder of Wikileaks

In addition, activists from the United States, Britain and elsewhere have promoted messages from far-right leaders, many of which are skeptical of the European Union.

"We're seeing foreign actors gain more of a voice in elections that are important to their interests," said Ben Nimmo, a senior fellow for information defense at the Atlantic Council, a think tank, who prepared the recent analysis about the Catalan referendum. "But it's not just state actors. More and more people are realizing that they can have an influence through social media."

A senior Spanish official told POLITICO that he had yet to see proof of Russia's influence in this weekend's referendum, but that did not mean such digital trickery was not happening.

Yuri Korchagin, Russia's ambassador to Spain, denied the country's involvement in the upcoming vote in an interview with Sputnik, a state-backed news outlet that has published several inaccurate articles about the referendum process in Catalonia.

"Russia is in no way connected to these processes and has no interest in being connected to them," he said in the interview.

The Catalan government did not immediately respond to requests for comment.

Assange amplified

As part of the recent misinformation campaign, Russian state news outlets including Sputnik have written misleading articles that have highlighted alleged corruption within the Spanish government, as well as quoting officials from North Korea about how to resolve the country's standoff over the Catalan referendum. The agency published more than 200 articles on the upcoming vote over the two weeks through September 27, according to the Atlantic Council's analysis, with both pro- and anti-referendum slants.

These Russian news agencies, as well as Russian users on Twitter, also repeatedly promoted the views of Julian Assange, the founder of Wikileaks, who has taken to social media to call for Spanish authorities to respect the upcoming vote in Catalonia.

"Spain's government acts like a banana monarchy — embarrassing for Europe!" he wrote on Twitter on September 19.

Catalan activists welcomed Assange's involvement in highlighting their campaign, particularly ahead of a standoff this weekend over whether the referendum will be allowed to take place.

But his pro-referendum stance also has been routinely shared by Sputnik and alleged networks of Russian social network bots.

On September 15, for instance, Assange posted a message on Twitter calling for Catalonia's right to self-determination. This post, according to an analysis of social media trends, was then retweeted massively within minutes of its publication, a potential sign that automated social network accounts — many with connections to Russia — promoted it.

This use of so-called online bots follows similar activities days before the German election earlier this month, when hundreds of accounts with links to Russia also boosted messages linked to Alternative for Germany, the far-right political party.

And in May, groups connected to the alt-right movement in the United States helped to share online messages in support of Marine Le Pen, the far-right French politician, in the run-up to France's presidential election.

In both countries, according to experts, it remains unclear how such messages from either state-backed or civilian international groups affected the overall outcome.

Yet the role of foreign actors, particularly across social media like Twitter and Facebook, aimed at swaying countries' local campaigns, is not likely to stop anytime soon.

"This type of misinformation is not new," said Tommaso Venturini, a researcher at the médialab of Sciences Po Paris, who tracked fake news during the French presidential election. "But what is new is that it now blurs the line between public debate and our private conversations online."