Facebook reports that most disinformation campaigns in the last four years came out of Russia.
Sarah Tew/CNET

Russia has been the main source of disinformation on Facebook since 2017, the social network said in a report Wednesday. The company has apparently uncovered disinformation campaigns in more than 50 countries in that period, and shut down 150 networks of fake accounts.

Aside from Russia, Iran, Myanmar, the US and Ukraine were top sources of fake news. The US, Ukraine, Britain, Libya and Sudan were the most frequent targets.

“Influence operations are not new, but over the past several years they have burst into global public consciousness,” it wrote in the report. “These campaigns attempt to undermine trust in civic institutions and corrupt public debate by exploiting the same digital tools that have diversified the online public square and empowered critical discussions from Me Too to the Black Lives Matter movements.”

The 2016 US presidential election was “a watershed moment” for disinformation, the report noted, but the techniques used then “are now harder to pull off, more expensive and less likely to succeed.” However, the people responsible for disinformation have found more subtle approaches like co-opting legitimate Facebook users.