It's in the millions.
Nearly 10 million Americans saw ads on Facebook that have since been linked to Russia and its alleged plot to influence the 2016 U.S. presidential election.
The statistic, revealed by Facebook on Monday, comes as the company takes fire for the role its automated advertising platform played in spreading the online ads.
Facebook said Sunday that it would deliver to U.S. lawmakers copies of the roughly 3,000 Russian-linked ads. In a blog post on Monday Facebook vice president of policy and communications Elliot Schrage explained some of the kinds of Russian-bought ads it was handing over to Congress.
Schrage said that the ads contained “divisive social and political messages across the ideological spectrum” and focused on “topics from LGBT matters to race issues to immigration to gun rights.” Schrage did not cite specific ads, of which 44% were seen prior to the U.S. presidential election on Nov. 8, with the remainder appearing after.
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Schrage defended Facebook’s automated advertising service, writing that it was “designed to show people ads they might find useful, instead of showing everyone ads that they might find irrelevant or annoying.” However, he acknowledged that Facebook fb now recognizes the potential to misuse the ad-targeting system and he reiterated Facebook’s earlier statement that it would hire an additional 1,000 people to review online ads and determine if they violate the company’s policies.
Schrage also said that Facebook is working with Google goog , Twitter twtr , and other unspecified technology companies to combat the spread of misleading online ads, although he didn’t reveal any specifics of their efforts. U.S. lawmakers have called on Google, Facebook, and Twitter to testify before Congress on the possible role their services played in distributing fake and deceptive information.
Facebook also “would have caught these malicious actors faster and prevented more improper ads from running” if it knew then what it knows now about how people can misuse the service. He also spoke about how the company’s improved tools to identify bogus ads would have helped.
“The ad transparency tool we’re building will be accessible to anyone, including industry and political watchdog groups,” Schrage said. “And our improved enforcement and more restrictive content standards for ads would have rejected more of the ads when submitted.”