At least 677,774 people in the United States followed, retweeted or liked content distributed by Russian government-linked Twitter accounts in a 10-week span prior to the 2016 U.S. election, Twitter announced Friday.
The social networking site also increased its tally of profiles linked to the Internet Research Agency, the organization behind the Russian propaganda effort, to a total of 3,814 accounts, responsible for 175,993 tweets over that same time period.
Those tweets were amplified by an additional 50,258 “automated accounts,” Twitter added, noting the propaganda they spread “represents a challenge to democratic societies everywhere.”
The company added, “We have since made significant improvements, while recognizing that we have more to do as these patterns of activity develop and shift over time.”
Twitter released five examples Friday of some of the Russian-backed content that received the most engagement, and pledged to notify via email those who had interacted with it:
Given Twitter’s relatively short 10-week timeframe for this analysis, it’s likely Russia’s reach was far greater. An investigation by Facebook spanning a two-year period before the election found similar content from Russia was seen by more than 126 million Americans.
This article originally appeared on HuffPost.