The panel also released 65 pages of Russia-linked Twitter accounts that have been taken down, including some that resembled news organizations and others that were retweeted by Trump campaign officials and President Trump himself.
Rep. Adam Schiff, D-Calif., said Wednesday the Russian campaign was designed "to further a broader Kremlin objective -- sowing discord in the U.S. by inflaming passions on a range of divisive issues."
The Russians "take a crack in our society and turn it into a chasm," Sen. Angus King, I-Maine, said at the Senate Intelligence Committee's hearing Wednesday morning, citing earlier testimony before the committee.
Representatives from Facebook, Twitter and Google, who testified before the two intelligence panels today and the Senate Judiciary Committee on Tuesday, said most of the ads focused on divisive social issues rather than specific candidates in the presidential election.
Among the sampling of 3,000 Facebook ads the committee released Wednesday included posts promoting the Black Lives Matter movement, Texas secession, the Second Amendment and cracking down on illegal immigration.
Speaking to the Senate Wednesday morning, top lawyers for Google, Facebook and Twitter admitted that efforts to combat Russian activity on their platforms during the election were insufficient and said that they still don’t have a full picture of the Russian online influence effort.
Senators went after the social media companies and highlighted the implications of the online meddling.
Facebook revealed earlier this week that Russian-linked content may have reached as many as 126 million American users on the platform during the 2016 U.S. presidential race. Facebook’s top lawyer said Wednesday that figure is closer to 150 million people when Russian content on Facebook-owned Instagram is included.
Twitter said it uncovered 2,752 accounts linked to the Internet Research Agency, a Russian “troll farm.” Google identified two accounts linked to the IRA that spent $4,700 on ads on Google platforms, and 18 YouTube channels connected to the Russian effort.
"We could've done more and we should've done more," Google senior vice president and general counsel Kent Walker said Wednesday.
Under pressure from Warner, the witnesses also admitted that Facebook, Twitter and Google do not yet have a full accounting of Russian activities on their platforms.
The company representatives highlighted steps the platforms have taken to address concerns about content on their sites. Facebook, for example, is adding 10,000 employees to its security team by next year, effectively doubling the size of its team.
Republicans repeatedly pointed out that the Russian effort was focused on more than the 2016 election.
Senators also pointed out that the Russian effort was sophisticated and went beyond fake ads.
Burr identified fake groups created in Texas -- one supporting Texas secession and another called "United Muslims of America" -- that created conflicting events at an Islamic center in Houston, with the goal of bringing conflicting groups together to foment unrest.
"What neither side could have known was that Russian trolls were encouraging both sides to battle in the streets," Burr said.
Democrats also pushed back on Trump’s dismissive comments about Russian interference efforts and called for more leadership on the issue from the White House.
"We have a president who remains unwilling to acknowledge the threat that Russia poses to our democracy," Warner said.
Members also expressed concerns about the company's algorithms and ability to weed out disinformation.
At the House hearing, Democrats questioned the company executives on the possibility of collusion between the Trump campaign and Russia. Rep. Jackie Speier, D-California, comparing Trump tweets and Russia Today posts that both mentioned Hillary Clinton's health, asked Twitter and Facebook if they had any evidence of the Trump campaign sharing Russian content, or Russian-linked accounts sharing Trump content.
Colin Stretch, Facebook's counsel, suggested the committee look into questions of potential collusion.
"We've provided all relevant information to the committee and we do think it's an important function of this committee because you do have access to a broader set of information that any single company will," he said.
Rep. Joaquin Castro, D-Texas, asked the companies if they would commit to sharing private messages between accounts on their platforms with the committee. Democrats in the House and Senate want to know who may have been communicating with Russian-linked accounts on Twitter.
Sean Edgett, Twitter's acting general counsel, said the company would respond to any request for direct messages through "the right legal process."