VIDEO - F.B.I. Is Investigating Trump’s Russia Ties, Comey Confirms - The New York Times

Mr. Comey said Russia used a murky network of government officials, oligarchs, business leaders and others close to Mr. Putin to gather intelligence. But he repeatedly sidestepped specific questions about Mr. Trump’s advisers, and acknowledged that American citizens sometimes did not realize they were talking to foreign agents. He said the existence of an investigation did not mean the F.B.I. would ever prove wrongdoing.

Nevertheless, Democrats repeatedly highlighted the Trump campaign’s Russian connections as they painted Mr. Trump as a candidate who adopted pro-Russia views and courted Russian interests.

“Is it possible that all of these events and reports are completely unrelated and nothing more than an entirely unhappy coincidence?” said RepresentativeAdam B. Schiff of California, the intelligence committee’s top Democrat. “Yes, it is possible. But it is also possible, maybe more than possible, that they are not coincidental, not disconnected and not unrelated.”

Mr. Comey, testifying for more than five hours, said there was no evidence that Russian hackers had changed any votes in the election. The statement was quickly spun by the White House, which posted that clip of Mr. Comey’s testimony on Twitter.

But later in the hearing, when Mr. Comey was read the tweet by Representative Jim Himes, Democrat of Connecticut, the F.B.I. director made it clear that that was not what he had said.

“We’ve offered no opinion, have no view, have no information on potential impact because it’s not something we looked at,” Mr. Comey said, clarifying that the intelligence community is examining what Russia did to interfere with the election, not the effect of that interference.

Mr. Comey did not say when he expected his investigation to end or whether he planned to make the results public, prompting Republicans to complain that prolonging it would keep a cloud over the White House.

“The longer this hangs out there, the bigger the cloud,” said Representative Devin Nunes of California, the Republican chairman of the Intelligence Committee. “If you have evidence, especially as it relates to people working in the White House or in the administration, that is information we really should know.”

Mr. Trump began the day with Twitter posts denying any collusion with Russia and criticizing leaks of classified information about the investigation. By midday, the White House was citing Mr. Comey’s testimony to suggest that members of the Obama administration had coordinated leaks against Mr. Trump.

Republicans on the Intelligence Committee made similar allegations, using their questions to Mr. Comey to criticize the news coverage about the Russia investigation and chastise government officials who speak anonymously to journalists. Mr. Nunes said he was particularly concerned about the anonymous sources who revealed to journalists that some of Mr. Trump’s associates were being investigated.

The White House has insisted that there is nothing left to investigate about Russia and has instead asked Congress to look into Mr. Trump’s claims that he was wiretapped by President Barack Obama. Mr. Trump made those allegations in a flurry of Twitter posts early this month.

The White House has stood by his accusation, even in the face of conclusions from all corners of the government that it is false. On Tuesday, Mr. Comey, who had asked the Justice Department if it would make a public statement refuting Mr. Trump’s claim, summarily dismissed it.

“I have no information that supports those tweets, and we have looked carefully inside the F.B.I.,” Mr. Comey said, adding that the Justice Department also had no evidence.

Those assurances seemed unlikely to change the White House’s position.

Asked Monday whether, in light of Mr. Comey’s testimony, the president stood by his assertion that he was wiretapped, Mr. Spicer said that he did.

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A version of this article appears in print on March 21, 2017, on Page A1 of the New York edition with the headline: Comey Confirms Inquiry on Russia and Trump Allies.