Facebook on Friday announced the removal of 82 pages, groups, and accounts linked to Iran, a majority of which had misrepresented themselves as being US citizens and posted on "politically charged topics," including immigration and race relations, as relevant to the United States.
In a blog post, the company's head of cybersecurity policy, Nathaniel Gleicher, said the accounts were first detected one week ago. US authorities, including members of Congress, were notified. A few of the accounts also mimicked UK citizens, Gleicher said.
"Despite attempts to hide their true identities, a manual review of these accounts linked their activity to Iran," he said. "We also identified some overlap with the Iranian accounts and Pages we removed in August."
Gleicher added that the investigation was in its early stages and no links have thus far been establishing tying the accounts to the Iranian government. "[W]e can't say for sure who is responsible," he said.
One of the pages had amassed 1.02 million followers, and one of the groups was joined by roughly 25,000 accounts. Instagram, which is owned by Facebook, also hosted one of the accounts, and it had amassed around 28,000 followers.
The accounts reportedly hosted seven events, but in total spent less than $US100 ($142) on advertisements across the platforms. A review of the content posted by the accounts has not yet been completed, Gleicher said.
One of the accounts, "Wake Up America," appears to have promoted memes and other graphics critical of President Donald Trump, including one labelling him "The Worst, Most Hated President in American History." Others posted by an account called "No racism no war" had posted images of Colin Kaepernick and a cartoon criticising Supreme Court Justice Brett Kavanaugh. Screenshots supplied by Facebook did not include dates or show how many times the images were liked or shared.
Gleicher credited Facebook's "elections war room" with having detected what the company calls "coordinated inauthentic behaviour."
"These groups helped quickly identify, investigate and evaluate the problem, and then take action to stop it," he said. "They will continue their investigations, including any additional information we get from law enforcement, other technology companies, or other experts."
In August, Facebook similarly removed hundreds of accounts from both Facebook and Instagram, some of which dated as far back as 2011. In this case, Facebook's investigation was prompted by a tip from the security firm FireEye, which found connections to Iranian state media.
Although Facebook would not say that any of these new accounts it deleted are tied to the Iran government, there was "some overlap" between them and the pages removed in August, Gleicher said.