In a double-barreled assault on the
Comey was the most senior U.S. law enforcement official to publicly debunk Trump's extraordinary charges, first made on Twitter on March 4, that President Obama had wiretapped him at Trump Tower.
“I have no information that supports those tweets, and we have looked carefully inside the FBI,” Comey told a drama-laced House Intelligence Committee hearing carried live for nearly five hours on cable TV. He added that the
But Comey’s rebuke of Trump, which was echoed by Adm. Mike Rogers, director of the
The FBI is investigating the "nature of any links between individuals associated with the Trump campaign and the Russian government, and whether there was any coordination between the campaign and Russia's efforts," Comey said.
The White House downplayed the investigation into possible collusion by Trump's aides with Russian authorities. "Investigating it and having proof of it are two different things," Sean Spicer, the White House spokesman, told reporters.
Comey said the investigation was undertaken as part of the FBI's counter-intelligence mission and includes "an assessment of whether any crimes were committed."
"I can promise you we will follow the facts wherever they lead," Comey said.
Comey and Rogers refused to say whether the FBI investigation, which began last July, had uncovered any evidence of improper collusion or potential crimes, saying it was inappropriate to discuss an ongoing investigation involving classified sources and information.
Even their limited disclosures raised the possibility that some of Trump's current or former aides could face lengthy investigations and potentially criminal prosecution, saddling the White House with a major scandal.
The national security chiefs' testimony clearly rattled the White House. During the hearing, President Trump tweeted that the FBI and NSA directors had confirmed that "Russia did not influence electoral process."
That led to an unusual exchange in the House hearing room, when Rep.
"It certainly wasn't our intention to say that today because we don't have any information on that subject," Comey said carefully.
Earlier Monday, Trump used Twitter to denounce the FBI investigation, as well as separate inquiries by the GOP-led House and
"There is no evidence of a Trump-Russia collusion and there is no evidence of a Trump-Russia scandal," the White House said later in a statement.
The investigation of a sitting president's campaign by the FBI raises serious procedural and constitutional issues.
Atty. Gen. Jeff Sessions already has recused himself from overseeing the FBI investigation after news reports disclosed he had met twice with Sergey Kislyak, Russia's ambassador to the United States, during the campaign but failed to tell the Senate during his confirmation hearing.
As a result, Acting Deputy Atty. Gen. Dana Boente will oversee the investigation. If he is confirmed by the Senate as deputy attorney general, Rod Rosenstein would be the last word in the case.
Comey is four years into his decade-long term. He can be fired by the president, though that surely would draw comparisons to the resignation of President Nixon's attorney general and the dismissal of the deputy attorney general in the so-called 1973 Saturday Night Massacre during the Watergate investigation.
Underscoring the delicacy of the situation, Comey repeatedly declined to answer lawmakers' questions about the investigation, Republicans' complaints about leaks to the media, or Democrats' attempts to draw him into discussion about which Trump aides might be involved.
"I cannot say more about what we are doing," Comey said.
The FBI director's testimony marked his second time at the center of a politically explosive investigation into the 2016 presidential campaign.
In July, he announced in a lengthy news conference that he was recommending no criminal charges be filed against Democratic nominee
On Oct. 28, less than two weeks before the election, Comey shook up the presidential race by notifying lawmakers that his agents had learned of additional Clinton emails in an unrelated case that "appear pertinent to the investigation."
Although he followed up several days later with a letter to say that the FBI had found nothing to change his earlier recommendation, Democrats blamed Comey for helping sink Clinton's campaign at a crucial point.
On Monday, he spoke in far less detail about the Trump inquiry than he did about the FBI investigation into Clinton. He refused to commit to providing an update or to say when the investigation would be completed.
"I don't know how long the work will take," he said
Comey and Rogers said they stood by a Jan. 6 report by the U.S. intelligence community that said Russian President
They also repeated that U.S. agencies did not try to assess whether the Russian effort, which included the hacking of Democratic National Committee computers and leaks of emails that embarrassed the Clinton campaign, had swayed public opinion or affected any votes on election day.
Both said they were surprised by the openness of the Russian operation.
"It's almost as if they didn't care that we knew what they were doing or that they wanted us to see what they were doing," Comey said. "It was very noisy, their intrusions in different institutions."
Republicans on the House committee focused their questions on leaks of classified information to the media about Trump's current and former aides, rather than on the investigation of Russian meddling.
Few offered any public defense of Trump's continued claims of wiretapping or of contacts between his aides and Russian authorities. Several sought to limit the political damage by questioning whether Putin actively sought to help Trump.
“Don't you think it's ridiculous to say the Russians prefer Republicans over Democrats?” asked Rep.
In contrast, Rep.
Several top Trump aides, including his former campaign manager, Paul Manafort, and his former national security advisor,
Other Democrats questioned Comey about the Trump team's removal of Republican Party platform language calling for arming Ukraine in its fight against pro-Russian separatists, as well former Trump advisor Roger Stone's contacts with pro-Russian hackers.
Several Democrats unsuccessfully pressed Comey to confirm some details in a dossier of unverified allegations against Trump and his associates that was written by a former British intelligence officer and made public in January by BuzzFeed.
"Is it possible that all of these events and reports are completely unrelated and nothing more than an entirely unhappy coincidence? Yes, it is possible," Schiff said. "But it is also possible, maybe more than possible, that they are not coincidental, not disconnected and not unrelated."
Schiff added that if Trump associates did collaborate with Russia, it would be a "potential crime" and "one of the most shocking betrayals of democracy in history."
"The name of a U.S. citizen that was supposed to be statutorily protected is no longer protected," Gowdy said.
"I don't want to confirm it by saying we are investigating," Comey said. "Be assured we are going to take it very seriously."