In the past six months, a growing body of evidence has revealed the extent to which the Kremlin used major social media platforms to influence the 2016 presidential election.

Russian-linked operatives bought hundreds of thousands of dollars worth of advertisements across Twitter, Facebook and Google, and impersonated Americans online to spread divisive content and fake news to real voters across the country. Critics say that the companies significantly underestimated the threat and that their response lacked urgency when it was revealed.

Below is a timeline of the aftermath of Russia’s interference in the election — told through the responses of the companies who unwittingly enabled it. From fake Facebook accounts to thousands of dollars in Twitter ads, it is a story of real-time reaction to a campaign of disinformation that is only just beginning to be understood.