President Trump learned from the top Republican on the House Intelligence Committee Wednesday that his communications may have been intercepted as a byproduct of legal surveillance by the federal intelligence community.

Trump said he felt “somewhat” vindicated by information that Intelligence Committee Chairman Devin Nunes, a California Republican, shared with him during a hastily scheduled White House meeting. The chairman said he became concerned while reading documents that indicated Trump’s communications and those of other Trump associates were swept up inadvertently, but in a manner that identified them.

Following his discussion with Trump, Nunes said the president was “concerned” and “would like to see these reports.” The chairman said he hoped the intelligence community would share the surveillance data with the White House, but he denied that Trump or his associates were targeted in any U.S. probe involving international figures or entities.

The committee’s leading Democrat, Rep. Adam Schiff, said Nunes’ unusual decision to share information with the president and House Speaker Paul Ryan before consulting committee members during an ongoing investigation was “beyond irregular” and justified an independent commission to pursue the facts “completely out of the political realm.”

The startling twists occurred two days after FBI Director James Comey told the House committee the bureau and the Justice Department found no evidence to support Trump’s March 4 tweets accusing President Obama of “wiretapping” him at Trump Tower last year. Comey disclosed publicly for the first time that beginning in late July, the FBI launched an investigation of Russia’s interference with the U.S. election, motivated by Moscow’s evident support for Trump and opposition to Hillary Clinton.

Despite widespread rejections of his assertions, Trump has not retreated. Obama, intelligence officials and lawmakers, including Nunes and Schiff, have all said Trump was not the subject of Obama administration wiretaps.

Former National Security Adviser Michael Flynn’s telephone contacts with the Russian ambassador during the Trump transition were incidentally intercepted by the intelligence community, leaked to the news media, and disclosed to Trump’s White House counsel by the Justice Department following the inauguration. The president said he fired Flynn weeks later because his national security adviser denied to Vice President Mike Pence that he spoke with Sergey Kislyak once the controversy erupted.

Nunes, a member of Trump’s presidential transition team, on Wednesday described what he recently learned as important enough to be folded into the committee’s existing investigation, rather than prompting a new House probe. But he also said privately sharing information with Trump on Wednesday did not scuttle the appearance of independence on his committee because the intercepts he saw did not deal with Russia.

“The reports that I was able to see did not have anything to do with Russia or the Russian investigation, or any tie to the Trump team,” Nunes told reporters. “It has everything to do with possible surveillance activities, and the president needs to know that these intelligence reports are out there, and I have a duty to tell him that.”

Nunes said he was concerned about the “unmasking” – identification – of Trump and others in the surveillance, but in announcing the contents of secret reports furnished to him, the chairman in effect publicly unmasked Trump on his own – and potentially revealed other details about what he said was a legal investigation involving foreign targets.

Nunes said the National Security Agency was cooperating with the committee.

Schiff, during an evening news conference, said Nunes’ comments were “confusing” and instantly put the committee’s bipartisan work in limbo. “The wrecking ball of this investigation has just claimed another victim, and that is this committee,” Schiff said.

The ranking Democrat said he had not seen the intercepts the chairman publicly described but believed “there is no evidence that any names unmasked were unmasked improperly” in secret surveillance reports.

Because Republican arm-twisting on both ends of Pennsylvania Avenue was also underway Wednesday in an effort to pass a health care bill this week, House Democrats said disclosures suggesting Trump was caught in a surveillance net supplied a convenient detour around GOP infighting, as well as FBI testimony early in the week.

House Minority Leader Nancy Pelosi said Nunes “cannot possibly lead an honest investigation,” and she called on the Republican majority to appoint an independent commission and transfer the investigation to a neutral body outside the legislative branch. (The Senate Intelligence Committee also is investigating similar terrain.)

Nunes conceded he had not advised Schiff or the committee’s minority members before he spoke to Capitol Hill and to White House reporters. He also said “a few dozen” reports he viewed referred to surveillance that may have been lawfully authorized under the Foreign Intelligence Surveillance Act, which requires a warrant issued by a FISA court judge.

Nunes said he wanted the NSA, FBI, and CIA to turn over requested surveillance information to the full House committee.

“What I’ve read bothers me, and I think it should bother the president himself and his team,” the chairman told reporters while standing in front of the West Wing entrance. “I think some of it seems to be inappropriate … It definitely goes beyond what happened to Gen. Flynn.”

Asked if Trump’s communications were among the incidental intercepts of surveillance he examined, Nunes responded “yes” and elaborated.

As part of the ongoing Russia probe, “We will continue to investigate anything and everything that continues to be caught up in this,” Nunes added.

House Democrats reacted with bewilderment and criticism, arguing that Nunes' public presentations undermined the work of the committee going forward.

Schiff suggested the chairman's visit to the White House, without having first briefed members of the committee, could be part of a broader campaign by the administration to distract from Comey's testimony Monday that placed the president and his former campaign advisers in the crosshairs of an FBI probe that could last months or years.

Schiff said Nunes must decide whether he would lead the investigation impartially or, "Is he going to act as a surrogate of the White House?"

Schiff said he was not given the report to which Nunes is referring, and could not make an assessment as to whether the chairman disclosed classified information.

But he called his colleague's move "deeply troubling" and said it "makes the most profound case for an independent commission." In a later interview with NBC News, Schiff raised the stakes of such an investigation, dangling that "there is more than circumstantial evidence now" of collusion, though he wouldn't elaborate.

Schiff's suggestion that the committee's work is now clouded presents a significant dilemma for its members. Next week, former Director of National Intelligence James Clapper, former CIA Director John Brennan, and former Deputy Attorney General Sally Yates are expected to testify.

The rebukes from Schiff and other Democrats represented an unexpected turning point in what had been described by both sides earlier in the week as a bipartisan and collaborative panel.

In an interview with RealClearPolitics on Tuesday, Schiff said the two men had worked well together, recognizing "this is the most high profile issue we've had to handle, and one that has intense political consequences."

Nunes and Schiff had pointed to their predecessors—Republican Mike Rogers of Michigan and Democrat C.A. “Dutch” Ruppersberger of Maryland— as lawmakers who restored the committee's aspirations for bipartisanship. They told RCP they wanted their tenures to follow that model.

Before Wednesday, Nunes and Schiff often convened joint press conferences in the Capitol to discuss the committee’s work.

But Wednesday, Schiff said he was caught off guard, and expressed alarm that Nunes briefed the speaker and Trump before contacting any other committee members.

"The chairman's actions and closeness to a president whose campaign is under federal investigation have gravely damaged the investigation's credibility," said committee Democrat Rep. Eric Swalwell.

Democratic Rep. Jim Himes, during a CNN interview, said Nunes' credibility has come under question before, pointing to a Washington Post report that described the chairman as among a team enlisted by the White House to defend the administration.

Meanwhile, some Intelligence Committee Republicans leaped to Nunes’ defense.

“The incidental collection, subsequent dissemination, and unmasking of individuals related to the Presidential transition team needs to be carefully investigated as there are real concerns about whether minimization procedures were appropriately followed," Republican Rep. Mike Turner said in a statement.

James Arkin contributed to this report.

Alexis Simendinger covers the White House for RealClearPolitics. She can be reached at asimendinger@realclearpolitics.com. Follow her on Twitter @ASimendinger.