WASHINGTON — Laura Cooper, the top Pentagon official overseeing U.S. policy regarding Ukraine, testified in front of House impeachment investigators on Wednesday after a five-hour delay caused by a group of House Republicans who stormed the secure room where the deposition was taking place.

The GOP members — who don’t sit on the committees that are questioning witnesses in the impeachment inquiry — occupied the secure room, known as a SCIF, in the basement of the Capitol Visitor Center for several hours.

According to multiple accounts from lawmakers, the Republicans, led by Rep. Matt Gaetz, R-Fla., burst in shortly after a morning press conference protesting the impeachment process as unfair. More than two dozen GOP members participated, a House Intelligence Committee official said. In what the official called a "major security breach," the Republicans brought their cellphones into the SCIF, which is not permitted. Some Republican members refused to comply with requests to remove those devices from the room, the official said.

House rules only allow members to participate in depositions if they serve on the committees holding the depositions, which in the case of the impeachment inquiry are the House Intelligence, Foreign Affairs and Oversight committees.

The House Parliamentarian ruled that the Republican members participating in the demonstration were in violation of House deposition rules, according to the Intelligence Committee official. Eventually, the lawmakers departed for regularly scheduled votes on the House floor. Cooper departed her deposition around than three hours after it began around 3:30 p.m. ET.

Intelligence Chairman Adam Schiff, D-Calif., whose panel has taken the lead in the impeachment inquiry, suggested that the demonstrations were a response to the nature of the testimony given a day earlier by Bill Taylor, the top U.S. diplomat in Ukraine.

Taylor told impeachment investigators that President Donald Trump directed officials to tie aid to Ukraine to demands that the country open an investigation into the Biden family and the 2016 election, a potentially serious blow to Trump's repeated denials of a quid pro quo.

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"Clearly the White House was devastated by yesterday's testimony, and these witnesses have been willing to defy the administration and follow the law and come testify," Schiff said. "So, the president's allies are trying to stop them through other means but they won’t be successful."

Cooper, a career member of the senior executive service, currently serves as the deputy assistant secretary of defense for Russia, Ukraine and Eurasia. The Defense Department previously told Congress that it wouldn’t comply with the impeachment inquiry.

"We’re grateful that the witness is a real professional and has come forward not withstanding the obstacles,” Schiff told reporters after she finally began testifying.

Lawmakers had been expected to question Cooper about the Trump administration's decision over the summer to withhold the assistance to Ukraine that had previously been appropriated by Congress, despite the Pentagon’s recommendation that it be distributed.

Republicans have argued for weeks that the process has been unfairly conducted behind closed doors with Democrats inhibiting their ability to ask questions. However, Schiff said last week that “Republicans have been completely represented” and that the time for questions has been equally divided between both sides.

"We go until the questions are exhausted. They get to ask any questions they want," he said.

Schiff also noted last week that there is precedent stemming from the Watergate era, as well as President Bill Clinton’s impeachment proceedings, for holding the initial investigation behind closed doors. He said that he anticipated a time when impeachment investigators will release the transcripts of the depositions, and that the House may call back some of those witnesses to testify in public.

On Wednesday, Rep. Andy Biggs, R-Ariz., and other members participating in the demonstration appeared to post tweets from inside the secure room. Biggs clarified that he was transmitting his missives to his staff to post.

Reporting from Adam Schiff’s secret chamber....



There are still about 15 Republican members in the SCIF, including @RepMattGaetz, @SteveScalise, @RepMarkWalker and myself. — Rep Andy Biggs (@RepAndyBiggsAZ) October 23, 2019

As part of a series of tweets, Biggs said that "when Republican members were in the SCIF, Chairman Schiff immediately left with the witness."

“Chairman Schiff threatened to file ethics complaints against remaining Republican members – not clear what exactly he would file or cite,” Biggs claimed.

Rep. Mark Walker, R-N.C., also appeared to tweet from the room.

UPDATE: We are in the SCIF and every GOP Member is quietly listening.



Meanwhile, Adam Schiff, clearly peeved that he will no longer be able to hide his impeachment sham, is threatening Ethics punishment for all of us.



His fake intimidation can’t hide his lies–Open the process! — Rep. Mark Walker (@RepMarkWalker) October 23, 2019

House Homeland Security Committee Chairman Bennie Thompson, D-Miss., said in a letter to the House Sergeant of Arms Wednesday that it was a "blatant breach of security" when Republicans took their cell phones into the SCIF and he called for action against them."

This unprecedented breach of security raises serious concerns for Committee Chairmen, including me, responsible for maintaining SCIFs," Thompson wrote. “As such, I am requesting you take action with respect to the Members involved in the breach. More broadly, I urge you to take House-wide action to remind all Members about the dangers of such reckless action and the potential national security risks of such behavior.”

Cooper’s deposition comes a day after what Democrats described as bombshell testimony from Taylor, who serves as chargé d'affaires in Ukraine. Michael Duffey, a politically appointed official in the White House budget office, was also scheduled to testify behind closed doors Wednesday but is not expected to appear after Office of Management and Budget acting Director Russell Vought announced that his office wouldn't cooperate with the probe.

According to a copy of his opening statement provided to NBC News, Taylor said that the U.S. ambassador to the European Union, Gordon Sondland, told him that while Trump was not requesting a "quid pro quo," he insisted Ukrainian President Volodymyr Zelenskiy publicly announce investigations into former Vice President Joe Biden and his son, Hunter, and matters relating to the 2016 presidential election.

Cooper previously served as principal director in the office of the assistant secretary of defense for homeland defense and global security affairs. She joined the Defense Department in 2001 and before that, worked at the State Department.