Mark Warner, Democrat of Virginia and vice chairman of the Senate Intelligence Committee, sharply criticized Twitter for not aggressively investigating its own systems to provide a more complete picture of Russian activities.
The sharp rebuke of Twitter came after FacebookÃ¢Â€Â™s admission to the two intelligence panels that it had connected 470 profiles and pages to a Russian company with ties to the Kremlin. Facebook also said the pages had placed 3,000 ads on Facebook at a cost of about $100,000.
The technology news site Recode reported earlier that Facebook had shared some details about Russian-linked profiles on its platform with Google, but the search giantÃ¢Â€Â™s investigation is expected to broaden beyond those leads, according to the person familiar with the matter.
What direction the congressional investigation into Google will take is not clear. Google is much larger than Facebook or Twitter, and it has a wide range of services that played a role in the dissemination of so-called fake news during the campaign.
But it is not a social network like Facebook or Twitter, making it harder for blatantly untrue stories to catch on, or for public sentiment to be stirred up through carefully targeted posts.
Google has, however, long dealt with people trying to game its search engine to highlight misleading information or use its AdSense advertising network to finance eye-catching but false news stories. YouTube is also fertile ground for offensive videos and misleading news stories.
Ã¢Â€ÂœWe will of course cooperate with inquiries; weÃ¢Â€Â™re looking into how we can help with any relevant information,Ã¢Â€Â Google said in a statement late Friday.
In April, Google said it had found that about 0.25 percent of its daily search traffic was linking to intentionally misleading, false or offensive information. The most prominent example occurred in the days after the election, when the top Google search result for Ã¢Â€Âœfinal election vote count 2016Ã¢Â€Â linked to a story that incorrectly said that Donald J. Trump, who had secured the presidency by winning the Electoral College, had also defeated Hillary Clinton in the popular vote.
In an effort to keep false stories out of its results and offensive suggestions out of potential search queries, Google started an initiative called Ã¢Â€ÂœProject OwlÃ¢Â€Â to provide Ã¢Â€Âœalgorithmic updates to surface more authoritative content.Ã¢Â€Â
Similar to the way content that receives more attention is often more heavily promoted on Facebook and Twitter, GoogleÃ¢Â€Â™s search engine gives more weight to results that are more frequently clicked on. It is one of hundreds of factors that go into ranking links.
The company has also been working on shutting access to AdSense for sites that spread misinformation. GoogleÃ¢Â€Â™s ad network is widely used by other websites and is often their only source of revenue. AdSense allows marketers to target users by different criteria, but it does not offer the same detail as Facebook, which can slice and dice its audience by their interests, including political leanings.
In late January, Google said it had permanently banned nearly 200 publishers from AdSense Ã¢Â€Â” a tiny number compared to the more than two million publishers registered on AdSense.
At the time, Google said it reviewed 550 sites Ã¢Â€Âœsuspected of misrepresenting content to users, including impersonating news organizationsÃ¢Â€Â in November and December and took action against 340 of them.