The European Union announced on Friday that it had proof of a "continued and sustained" disinformation campaign coming from Russia during the bloc's elections last month.

EU Security Commissioner Julian King said that "Russian sources" had used social media accounts, bots and fake news sites to target countries where populists have been gaining ground, like Poland.

"The number of disinformation cases attributed to Russian sources ... doubled as compared to the same period a year ago," King said, presenting a report compiled by investigators working for the European Commission.

According to the report, "available evidence has not allowed us to identify a distinct cross-border disinformation campaign from external sources specifically targeting the European elections."

"However, the evidence collected revealed a continued and sustained disinformation activity by Russian sources aiming to suppress turnout and influence voter preferences."

When asked by a journalist if this meant the report contradicted itself, King clarified that the election meddling campaign was "increasingly locally focused" rather than broadly scaled.

The report also noted a strikingly high number of websites and social media accounts expressing anti-migrant and anti-Islam sentiments.

'No big bang moment'

Justice Commissioner Vera Jourova said there was "no big bang moment" like the Facebook-Cambridge Analytica scandal that had drawn EU investigators' attention to the manipulation.

Read more: Facebook's Cambridge Analytica data scandal: What you need to know

The report also found that candidates who had benefited from the disinformation campaign played up the storylines provided by Russian sources.

A prominent Twitter account used as part of the effort suggested that the entire EU project had Nazi roots. Other examples included stories linking the accidental fire at Notre Dame cathedral in Paris to the decline of so-called Western Christian values and accusations that the "European deep state" was responsible for the collapse of the conservative and far-right coalition government in Austria.

King and Jourova said that tech giants like Google, Facebook and Twitter should be more forthcoming with authorities about where "malicious actors" are operating from.

While Internet companies tried to adhere to the voluntarily agreed Code of Practice, Jourova said they were not always successful: "Millions of false, computer-generated user accounts, so-called bots, have been shut down. But a lot more must be done to find fake news."

es/amp (AFP, dpa)

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