The company, which identified the pages two weeks ago and has since removed them, said in June that it had found no such activity. It said, for example, the posts on the year-old, feminist Resisters page "took a liberal or left-wing stance on issues around gender, race, immigration, and human rights".
But after Facebook's announcement, the White House stressed Trump opposed all efforts at election interference. The page also briefly listed an IRA account as one of its administrators.
However, it's still unclear whether the latest pages were directly tied to Russian Federation.
It said the "bad actor" accounts on the world's biggest social network and its photo-sharing site Instagram could not be tied directly to Russian actors, who American officials say used the platform to spread disinformation ahead of the 2016 U.S. presidential election.
The company noted that the users had gone to great lengths to cover their tracks.
"We will update this post with more details when we have them, or if the facts we have change". None had Russian IP addresses, the unique number ever computer or server has which allows its location to be discovered.
One of the administrators for a fake account was associated with "known IRA assets", whose access to Facebook was terminated seven minutes later.More news: Facebook CEO Zuckerberg loses $16b in 5 minutes
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"Today's disclosure is further evidence that the Kremlin continues to exploit platforms like Facebook to sow division and spread disinformation", Warner said in a statement Tuesday.
On a conference call with reporters this month, Gleicher declined to directly answer questions about whether the company had detected additional Russian information campaigns.
Facebook A sample of the posts from "Aztlan Warriors" and "Resisters", two pages Facebook identified as inauthentic. Those numbers may sound small, but their influence is spreading: More than 290,000 accounts followed at least one of the suspect pages, the company said. Additionally, the creators paid approximately $11,000 to run 150 ads on Facebook and Instagram. It's one of thirty total events the pages have organized, said Nathaniel Gleicher, Facebook's head of cybersecurity policy, some of which have already taken place.
Because Facebook did not name the event, it is unclear if it happened or not.
Some of the content published Tuesday by Facebook was racially loaded, and some of it was anti-Trump.
On the call, Facebook executives said they are sharing the evidence they found with law enforcement, which can help make a determination about the groups' motive and impact.
The perpetrators in this case took more trouble to cover their tracks, using VPNs and third-party companies to post the ads, so it'd be hard to say with certainty who implemented the campaign. The pages and accounts were connected to protests planned in Washington next week, Facebook said. This is the kind of thing we apparently are expected to get exercised about, but if "bad actors" can't do orders of magnitude more than this, they are trivial. In February, the U.S. Justice Department indicted 13 Russian nationals, and the St. Petersburg-based Internet Research Agency, for interfering in the 2016 U.S. election. But security is not something that's ever done. "We face sophisticated and well-funded adversaries, including nation states, that are always evolving and trying new attacks". It said that the company has shared the information with USA law enforcement agencies, Congress, other technology companies, and the Atlantic Council's Digital Forensic Research Lab.