Facebook and Twitter both announced on Thursday they had taken down hundreds of accounts believed to have been part of coordinated influence operations from Iran, Russia and Venezuela.

Facebook removed 783 pages, groups and accounts that it said posed as local actors in countries across Europe, the Middle East and south Asia and shared content that was largely repurposed from Iranian state media. The accounts, some of which had been active since 2010, had garnered about 2 million followers on Facebook and more than 250,000 followers on Instagram.
https://www.theguardian.com/technology/2019/jan/31/facebook-and-twitter-removed-hundreds-of-accounts-linked-to-iran-russia-and-venezuela

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Facebook removes 783 fake pages, accounts tied to Iran
Facebook says it has removed 783 Iran-linked pages, accounts and groups from its service for what it calls “coordinated inauthentic behavior.” That’s the social network’s term for fake accounts run with the intent of disrupting politics and elections.

Facebook has been disclosing such purges more regularly in recent months, including ones linked to groups in Myanmar, Bangladesh and Russia.
https://apnews.com/387e38a113b041ac9022093577b4ad8a

Foreign efforts to influence 2018 U.S. elections on Twitter 'limited' – company
Twitter Inc took down nearly 6,000 tweets during last November’s U.S. congressional elections, most of which were attempting to suppress the vote through intimidation or sharing false information, the company said on Thursday.

Most disinformation around the elections originated inside the United States, the company said, though it also identified “limited operations” to influence voters potentially connected to sources in Iran, Venezuela and Russia.
https://uk.reuters.com/article/uk-usa-election-twitter/foreign-efforts-to-influence-2018-u-s-elections-on-twitter-limited-company-idUKKCN1PP2W9
https://in.reuters.com/article/usa-election-twitter/foreign-efforts-to-influence-2018-u-s-elections-on-twitter-limited-company-idINKCN1PP2T5