One of the main tools for spreading false information was the Swedish language version of the state-funded news website, Sputnik News, one of the reports co-author's Sebastian Åsberg told Radio Sweden.
The website was active between spring 2015 and spring 2016, publishing nearly 4,000 articles.
There were highly negative articles about NATO or the EU for example, the migration policies of the EU,” Åsberg said. “And then there are the forged documents and letters which were very interesting as well, they started emerging quite a lot in 2015 and 2016.”
The report also said that armies of trolls were targeting journalists and academics on social media and that mainstream media sources had wittingly, or unwittingly, spread disinformation.
Åsberg said it was difficult to know how effective the campaign had been, but told Radio Sweden that notable falsehoods had appeared in debates about NATO membership ahead of a decision in Parliament.
He said he thought there were several motives for targeting Sweden but the main reason was to minimise NATO's role in the Baltic region, adding that the upcoming general election in Sweden next year could also trigger a new campaign.
The hacking of the Democratic Party e-mails in the run-up to the US presidential election has topped headlines around the world, and according to David Lindahl, a research engineer at the Swedish Defence Research Agency, Sweden should be prepared for the possibility that something similar could happen here ahead of the 2018 general election.
I would say it is a near-certainty", he told Radio Sweden, "Sweden in general has been quite naïve, security-wise".
Politicians in Sweden should always assume that someone is keeping track of where their telephone is, he adds.
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