Facebook and Twitter said on Tuesday that they have deleted fake accounts impersonating political candidates and journalists used as part of a pro-Iran social media campaign.

Facebook said it has removed 51 accounts, 36 pages and seven groups on its social media platform as well as three accounts from its Instagram service.

The accounts were run by people who "misled people about who they were and what they were doing," the social media giant said in a statement written by Nathaniel Gleicher, its head of cybersecurity policy.

Facebook said it had concluded that the social media activity had originated in Iran.

Twitter said in a statement that it removed a network of 2,800 inauthentic accounts originating in Iran at the beginning of May, adding that its investigation was ongoing.

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Pro-Iran, anti-Trump

Facebook said that the decision to delete the accounts came after it investigated a tip from FireEye, an internet security firm.

Read more: Facebook bans extremists, 'dangerous individuals'

FireEye said in a blog post on Tuesday that a network of social media accounts utilized fake American personas to spread messages in support of Iran and against US President Donald Trump around the 2018 congressional elections.

The accounts included ones impersonating a handful of Republican political candidates that ran for House of Representative seats in last year's midterm elections.

Lee Foster, a researcher with the California-based firm, said he found some of the fake personas, often ones claiming to be American journalists, had successfully convinced several US news outlets to publish letters to the editors, guest columns and blog posts. The writings displayed both progressive and conservative views, covering topics such as the Trump administration's designation of Iran's Revolutionary Guard as a terrorist organization.

"We're assessing with low confidence that this network was organized to support Iranian political interests," said Foster. "However, we're not at the point where we can say who was doing it or where it's coming from. The investigation is ongoing."

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dv/se (AFP, dpa, Reuters)

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