The "collusion issue is still open", said Republican Senator Richard Burr, standing alongside the committee's top Democrat, Mark Warner. But he added that Russian intelligence could threaten the next round of congressional elections next year.
Burr characterized the 2016 attempts by Moscow as a "very expansive network of Russian interference" that wanted to "create chaos at every level".
"They were indiscriminate", Burr said of the ads and other social media activity.
But he added that it "had hit a wall" in its efforts to talk to Christopher Steele, the former United Kingdom intelligence officer whose reports on allegations of active collusion involving Trump himself have become part of the continuing investigations being conducted by the Senate, House of Representatives, and the special counsel, Robert Mueller. "The committee can not really decide the credibility of the dossier without understanding things like who paid for it, who are your sources and sub-sources".
"I can compel you to come", Burr warned, hinting strongly that the committee was nearing the point of issuing a subpoena for Steele.
Steele is reported to have spoken to Federal Bureau of Investigation officials about his findings and given them information on his sources.
"We understand more about how our service was abused and we will continue to investigate to learn all we can".
Over the past eight months, Burr said, the committee has conducted over 100 interviews that yielded almost 4,000 pages of transcripts. Burr and Warner are keeping their committee clear of that question, and another panel, the Judiciary Committee, has locked horns with the Justice Department about getting witnesses for its own inquiry.
Regarding the memos that James Comey, the former FBI director, wrote about Trump's attempts to end the investigation into his former national security adviser, Michael Flynn, Burr said "the committee is satisfied that this issue has reached a logical end" as it related to the committee's Russian Federation investigation.
"The 2016 U.S. election was the first where evidence has been widely reported that foreign actors sought to exploit the internet to influence voter behavior", Schrage wrote.
While both Burr and Vice Chairman Sen. Only an interview with the former British intelligence officer who produced it, Christopher Steele, could help move things forward, Burr said, but Steele has not agreed to talk.
Warner also said that the Russian intelligence service activities did not end with the USA presidential election on November 8 and that similar acts continued ahead of political elections in Montenegro, Belgium, France, and Germany.
Congressional investigators are also examining how Russian Federation used Facebook, Twitter, and Google to target political ads and spread misinformation during the election. Some of the Russian-bought Facebook ads specifically targeted swing states like Michigan, Wisconsin, Ohio and Florida, as well as other states whose Electoral College votes were not truly contested during the election, a source familiar with the matter told CNN.
On 6 September, Facebook revealed a Russian-based influence operation had purchased $100,000 worth of ads to promote divisive political and social messages during the presidential campaign. CNN reported Wednesday that some of the ads specifically targeted MI and Wisconsin, two states that were critical to President Donald Trump's victory.
Burr said his committee will not release the ads but encouraged Facebook to do so.
Russia Today, the Kremlin-backed television network, spent $274,000 on more than 1,800 tweets on Twitter's network that "definitely or potentially targeted the USA market" during the 2016 presidential campaign, Twitter officials have also said.