Facebook removes 'misinformation' accounts linked to Iran and Russia

Facebook announced on Tuesday that it stopped stealth misinformation campaigns from Iran and Russia, by shutting down accounts as part of its battle against "fake news".

The social media giant removed more than 650 pages, groups and accounts identified as "networks of accounts misleading people about what they were doing", Chief Executive Mark Zuckerberg said. 

US law enforcement agencies have been notified, with content from some Facebook pages traced back to Iran. Others were linked to groups previously with ties to Russian intelligence operations, the social network said.

"We believe they were parts of two sets of campaigns," Zuckerberg said.

The accounts - some of which were on Facebook-owned picture sharing app Instagram - purported to be independent news or civil society groups.

Investigations revealed that they were in fact working as part of coordinated efforts, social network firm executives told reporters.

The investigation was prompted by a tip from cybersecurity firm FireEye regarding a collection of "Liberty Front Press" pages on Facebook.

Pages were also linked to Iranian state media, according to head of policy Nathaniel Gleicher.

Among the banned accounts was a "Quest 4 Truth" account claiming to be that of an independent Iranian media group. Investigations revealed that it was linked to Press TV, an English-language news network affiliated with Iranian state media, Gleicher said.

The first "Liberty Front Press" accounts found were at Facebook were created in 2013 and posted primarily political content focused on the Middle East but also featured news from the UK, Latin America and the US.

Facebook also removed a set of pages and accounts linked to sources the US government previously identified as Russian military services, according to Gleicher.

"While these are some of the same bad actors we removed for cybersecurity attacks before the 2016 US election, this more recent activity focused on politics in Syria and Ukraine," Gleicher said.

The accounts were associated with "Inside Syria Media Center" - which the Atlantic Council and other organisations have identified as covertly spreading pro-Russian and pro-Assad content.

"We ban this type of behaviour because authenticity matters, and people need to trust what they see on Facebook," Zuckerberg said.

Last month, Facebook shut down more than 30 fake pages and accounts involved in what appeared to be a "coordinated" attempt to sway public opinion on political issues ahead of November mid-term elections, but did not identify the source.

It said the "bad actor" accounts on the world's biggest social network and its photo-sharing site Instagram could not be tied to Russia, which used the platform to spread disinformation ahead of the 2016 US presidential election.