Facebook once again has been the target of a political influence campaign, months ahead of the November midterm elections.
The social network said Tuesday it removed 32 pages and accounts from Facebook and Instagram for "coordinated inauthentic behavior," which echoed Russian efforts leading up to the 2016 presidential election to sow discord in American society.
Facebook said it has yet to identify the groups or persons behind the interference because the perpetrators used software and internet phone services to cover their tracks.
The Menlo Park tech company said it is working with law enforcement and has notified outside researchers and Congress.
"Clearly whoever set up the accounts went through much greater lengths," Facebook chief operating officer Sheryl Sandberg said in a conference call with reporters Tuesday. "We face determined, well-funded adversaries."
Facebook declined to characterize the political motives of the removed pages and accounts, but shared a handful of examples that focused on progressive and liberal causes.
One page was called "Aztlan Warriors," which posted a meme of Native American historical figures such as Crazy Horse and Geronimo that read: "Giving thanks, to our vets in the 500 year war against colonialism."
Another page called "Resisters" shared a post that said "Women don't have to" and listed various traits such as "be thin," "cook for you" and "wear makeup."
It remains possible that the coordinated effort is being led by Russia's Internet Research Agency, whose operatives were indicted in February by special counsel Robert S. Mueller III for interfering with the 2016 election. Facebook said the Internet Research Agency was found to be a co-administrator of one of the removed pages for seven minutes before leaving.
The suspicious activity wasn't confined to the internet. Facebook said the inauthentic pages and accounts also organized 30 events, only two of which had yet to take place.
Half the events had fewer than 100 accounts expressing interest in attending. The largest event drew interest from 4,700 accounts and commitments to attend from 1,400 users.
One event, which was called "No Unite the Right 2 � DC," was scheduled for Aug. 10 in Washington to protest a follow-up to last year's deadly white supremacist rally in Charlottesville, Va.
It was organized by "Resisters" and co-hosted by five legitimate pages that shared information about how to take transportation to the event.
A total of 290,000 accounts followed at least one of the now-removed pages, the earliest of which was created in March 2017. The most recent one was created in May.
The majority of the followers belonged to four accounts: "Aztlan Warriors," "Black Elevation," "Mindful Being" and "Resisters."
The removed pages and accounts created 9,500 posts and collectively ran about 150 ads at a cost of $11,000 on Facebook and Instagram, which was paid for in U.S. and Canadian dollars.
