Facebook says it has removed 783 Iran-linked pages, accounts and groups from its service for what it calls "coordinated inauthentic behaviour".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. Twitter also said on Thursday that it "found limited operations" that may have been connected to sources in Iran, Venezuela, and Russia. It did not give further details and said it suspended the suspicious accounts before the 2018 US midterm elections.The accounts on Facebook and Instagram typically misrepresented themselves as locals in more than two dozen countries, ranging from Afghanistan, Germany, India, Saudi Arabia and the US, often using fake accounts and posting news stories on current events. This included using stories from Iranian state media about conflicts in Syria and Yemen.Facebook said on Thursday the accounts spent about $30 000 on advertisements, paid for in US dollars, British pounds, Canadian dollars and euros.The company said Twitter helped its investigation by sharing information about suspicious activity it found on its own service. The companies, along with others in the tech industry, have been cooperating more when it comes to such account takedowns by sharing information.Such cooperation can help the companies avoid regulatory scrutiny by showing critics and lawmakers that they can set aside differences when it comes to battling outside threats that affect their users.