Facebook says a Russian group posted more than 80,000 times on its network during and after the 2016 election, potentially reaching as many as 126 million users.
The company plans to disclose these numbers to the Senate Judiciary Committee on Tuesday, as part of congressional probes of Russian election interference, according to a person familiar with the testimony.
Twitter plans to tell the same committee that it has uncovered and shut down 2,752 accounts linked to the same group, Russia’s Internet Research Agency, which is known for promoting pro-Moscow messages.
And Google announced in a blog post that it found evidence of “limited” misuse of its services by the Russian group, as well as some YouTube channels that were likely backed by Russian agents.
The three companies will testify at three hearings on Tuesday and Wednesday.
Colin Stretch, Facebook’s general counsel, plans to tell the Judiciary panel that 120 pages set up by the Russian agency posted repeatedly between January 2015 and August 2017.
The company estimates that roughly 29 million people were directly “served” posts in their news feeds from the agency over that time.
Those posts then spread widely on Facebook, although Stretch’s prepared testimony makes clear that many of the 126 million people reached this way may not have seen the posts.
These “organic” posts that appeared in users’ news feeds are distinct from more than 3,000 advertisements linked to the agency that Facebook has already turned over to congressional committees.
The ads – many of which focused on divisive social issues – pointed people to the agency’s pages, where they could then like or share its material.
On Twitter, the Russia-linked accounts put out 1.4 million election-related tweets from September through to November 15 last year – nearly half of them automated.
The company also found nine Russian accounts that bought ads, most of which came from the state-backed news service Russia Today, or RT.
Twitter said last week it would no longer accept ads from RT and Sputnik, another state-sponsored news outlet. It will donate the $1.9 million it has earned from RT since 2011 to support external research into political uses of Twitter.
Google said that two accounts linked to the Russian group spent $4,700 on ads on its platforms during the 2016 election.
The company also found 18 YouTube channels likely backed by Russian agents. Those channels hosted 1,108 videos with 43 hours of material, although they racked up just 309,000 views in the US between June 2015 and November 2016.
The companies have been under constant pressure from Congress since it was first revealed earlier this year that Russians had infiltrated some of their platforms.
All three firms are expected to face questions about what evidence of Russian interference they found on their services, as well as why they did not find it earlier.