The Post report notes that these entities allegedly helped perpetuate claims about Hillary Clinton's health and connections with financiers through what it calls "Russia's increasingly sophisticated propaganda machinery — including thousands of botnets, teams of paid human 'trolls,' and networks of websites and social-media accounts."
Two separate research groups studied this issue; one is the Foreign Policy Research Institute whose fellow Clint Watts is quoted as saying, "They [Russians] want to essentially erode faith in the U.S. government or U.S. government interests."
The other is the organization PropOrNot whose forthcoming report is said to have found 200 websites that were disseminating Russian propaganda to more than 15 million people in the U.S. and related Facebook stories which are estimated to have been viewed at least 213 million times.
The research teams reportedly came to these conclusions, in part, by analyzing the origins and wording of messages on social media and other websites.
The Russians have denied any involvement in the U.S. election or in perpetuating fake news stories.