Facebook said that it's removed pages and content originating in Iran and Russia for "coordinated inauthentic behavior," the social network's latest effort to clean up the site in the aftermath of the 2016 election.
The company said in a blog post on Tuesday that it's removed 652 pages, groups and accounts, which targeted people in the Middle East, Latin America, U.K. and the U.S.
"These were distinct campaigns and we have not identified any link or coordination between them," the company said. "However, they used similar tactics by creating networks of accounts to mislead others about who they were and what they were doing."
Facebook's latest update on election meddling and platform abuse comes a month after it revealed a coordinated misinformation campaign around the coming midterm elections in November. The company said in July that it had removed 32 fake accounts and pages from both Facebook and Instagram after finding evidence of what Facebook called "inauthentic behavior."
In a call with reporters after Tuesday's blog post, CEO Mark Zuckerberg said that it's as important for Facebook to build relationships with law enforcement, governments and other countries to exchange information as it is for the company to develop its own tools for weeding out problematic content.
"We think that there's a lot of good work happening on both of those fronts," he said. "This is a top priority for our company."
A Facebook spokesperson said on the call that the company had originally planned to release the new information on Thursday, but moved up the announcement.
Facebook is continuing to deal with sophisticated abuse on the platform following the 2016 presidential election, when the Kremlin-linked Internet Research Agency purchased ads on the site that ultimately reached as many as 126 million users. Facebook previously declined to say whether the activity it detected was also carried out by Russian agents, though the tactics were similar. The accounts typically operated under fake identities, posting incendiary comments around political and social issues and organizing real-world events.
On Tuesday, Facebook revealed that in July it was given a tip from cybersecurity firm FireEye about a network of pages and accounts called "Liberty Front Press." Facebook began an investigation, which identified additional related pages and accounts with a link to Iranian state media. The first ones were created in 2013.
"Some of them attempted to conceal their location, and they primarily posted political content focused on the Middle East, as well as the UK, US, and Latin America," Facebook said. "Beginning in 2017, they increased their focus on the UK and US. Accounts and Pages linked to 'Liberty Front Press' typically posed as news and civil society organizations sharing information in multiple countries without revealing their true identity."
The group had 74 pages, 70 accounts and three groups on Facebook as well as 76 accounts on Instagram. Some 155,000 accounts followed at least one of the pages, and from January 2015 through August 2018, more than $6,000 was spent on Facebook and Instagram ads, paid for in U.S. and Australian dollars.
There were two other parts of Facebook's investigation. One identified the link between "Liberty Front Press" and other accounts posing as news organizations, attempting to hack user accounts and spreading malware. The other uncovered accounts and pages that mostly shared content about Middle East politics as well as politics in the U.K. and U.S.
Facebook has overhauled its advertising platform, ramped up content moderation and hired additional third-party reviewers as a result of the recent coordinated campaigns. It's touted successes in more recent global elections, like the French and Mexican contests as evidence of its improved detection capabilities.
— CNBC's Sara Salinas and Jordan Novet contributed to this report.