Facebook said the ads addressed social and political issues and ran between 2015 and 2017.
"The big picture is that we're stepping up tomorrow to help Congress understand foreign interference on the ad platform and to make improvements to the ad platform to enhance transparency", said Joel Kaplan, Facebook's vice president for USA public policy.
Facebook provided Congress with copies of 3,000 Russian-bought political ads on Monday, giving lawmakers a clearer picture into how a pro-Kremlin troll farm used social media to meddle in American politics. The company is working with Congress, the Special Counsel (who is looking into all matters relating to possible Russian influence on the elections) and its tech industry partners, including Twitter and Google, on the investigation.
The House Intelligence and Senate Intelligence Committees will hold hearings on the matter.
Facebook announced the hiring increase along with new initiatives to improve authenticity and transparency of its advertising, notably with more disclosures on political ads. Over $100,000 were spent on politically divisive ads over a two-year period ending in May.
"If someone self-identified as a "Jew-hater" or said they studied how to burn Jews in their profile, those terms showed up as potential targeting options for advertisers", the Facebook COO wrote.
Also, Facebook said it will add 1,000 workers to its global ads review team and invest more in machine learning to better understand when to flag and take down ads.
Although the ads reached 10 million people, they were relatively cheap.
"I don't have the answers to those questions". "I don't want anyone to use our tools to undermine democracy - that's not what we stand for".
The company said its automated advertising system is created to target users most interested in the topic of the messages.
As of late last week, Facebook was still in the process of handing over all of the ads to congressional investigators, according to a source familiar with the Facebook investigation, CBS News' Jeff Pegues reported.
The figure, disclosed by Facebook for the first time on Monday, underscores how effective Russian meddling on social media could be with even a minimal investment.
3,000 ads generated by accounts controlled by entities in Russian Federation have gone under the scanner, and Facebook has promised increased transparency on political ads in the future.
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