Social media giant Facebook estimates that Russian-backed "inflammatory" content reached as many as 126 million American users, roughly one-third of the nation's population, during and after the 2016 presidential election.
Twitter and Google, which own other popular social media tools, also had similar experience of being encroached upon by Russia-backed groups that tried to influence the elections.
The US accused Russia of meddling in 2016 presidential election in which Donald Trump emerged victorious.
Top officials of the three companies are scheduled to testify before the Senate Judiciary Committee later today during which they are likely to inform the lawmakers that the figures of Russian penetration in the American social media is much more than previously seen, said multiple media outlets having access to their testimonies.
Facebook will tell Congress that some 126 million US users, a potentially large portion of the voting public here, may have seen stories, posts or other content from Russian sources, according to the Wall Street Journal and other US media.
"Russian agents intending to sow discord among American citizens disseminated inflammatory posts that reached 126 million users on Facebook, published more than 131,000 messages on Twitter and uploaded over 1,000 videos to Google's YouTube service," according to copies of prepared remarks from the companies that were obtained by The New York Times.
The new information goes far beyond what the companies have revealed in the past and underline the breadth of the Kremlin's efforts to lever open divisions in the US using American technology platforms, especially Facebook, the daily said.
In a blog post, Google said that it found that two accounts linked to the Internet Research Agency spent a total of USD 4,700 on its platforms during the 2016 election cycle.
This figure covers both search and display advertisements.
Google said it found 18 channels likely associated with this campaign that made videos publicly available, in English and with content that appeared to be political.
There were 1,108 such videos uploaded, representing 43 hours of content and totalling 309,000 US views from June 2015 to November 2016.
These videos generally had very low view counts; only around 3 per cent had more than 5,000 views. These channels have been suspended by Google.
In its investigation, Facebook found that the Russia- backed Internet Research Agency' purchased 3,000 advertisements in USD 100,000.
It also found that 120 pages were created by the group to disseminate its advertisements and posts. The company had previously said that it found 470 total accounts linked to the Internet Research Agency.
Similarly, Twitter found as many as 2,752 accounts associated with Internet Research Agency.
"The new disclosures come as the tech industry is facing the threat of regulation. Tech companies are expected to face tough questions about their advertisements disclosure policy and their opposition to greater regulation," the journal said.
"The foreign interference we saw is reprehensible and outrageous and opened a new battleground for our company, our industry and our society," Colin Stretch, General Counsel of Facebook said in his prepared testimony.