https://www.theguardian.com/technology/2017/sep/21/facebook-adverts-congress-russia-trump-us-election

Mark Zuckerberg says providing ads will ‘help government authorities complete the vitally important work of assessing what happened’ in the election

Facebook will provide to Congress the contents of 3,000 advertisements purchased by Russians during the 2016 US presidential race, Mark Zuckerberg announced on Thursday following weeks of scrutiny surrounding the social network’s potential role in influencing elections.