WASHINGTON (Reuters) - A whistleblower report released on Thursday said President Donald Trump not only abused his office in attempting to solicit Ukraine’s interference in the 2020 U.S. election for his political benefit, but that the White House tried to “lock down” evidence about that conduct.

In a report released by a Democratic-led congressional committee, the whistleblower said White House officials intervened to shift records of a controversial phone call between Trump and Ukraine’s president from the computer system on which they would normally be stored.

“Instead the transcript was loaded into a separate electronic system that is otherwise used to store and handle classified information of an especially sensitive nature,” the report said. “One White House official described this act as an abuse of this electronic system because the call did not contain anything remotely sensitive from a national security perspective.”

The whistleblower is a CIA officer and was assigned at one point to work at the White House, two sources familiar with the probe into his complaint said. The New York Times first identified the whistleblower as a CIA officer, which Reuters confirmed.

House of Representatives Speaker Nancy Pelosi accused the president of involvement in a cover-up to hide details of his attempts to persuade Ukraine to investigate former Vice President Joe Biden, a leading Democratic presidential contender ahead of the 2020 election.

Trump reacted with fury on Thursday and assailed Pelosi’s Democrats for launching an impeachment inquiry into him this week over the Ukraine affair.

Trump told staff from the U.S. mission to the United Nations he wanted to know who provided information to the whistleblower, according to an audio recording provided to the Los Angeles Times by an attendee.

“I want to know who’s the person, who’s the person who gave the whistleblower the information. Because that’s close to a spy,” Trump can be heard saying on the recording.

“You know what we used to do in the old days when we were smart? Right? The spies and treason, we used to handle it a little differently than we do now,” Trump said.

The White House did not dispute the comments.

A joint statement by three Democratic House committee chairmen - Adam Schiff of Intelligence, Eliot Engel of Foreign Affairs and Elijah Cummings of Oversight - said Trump’s “threats of violence” constituted “reprehensible witness intimidation.”

Democratic Representative Raja Kirshnamoorthi, a member of the Intelligence Committee, said it was essential that the committee hear from the whistleblower.

“We need to talk to the whistleblower at the earliest, because I am concerned at some of the statements the president has been making about the whistleblower, and whether he’s going to retaliate against the guy,” he said.

On July 25, Trump pressed Ukrainian President Volodymyr Zelenskiy to investigate Biden and his son, according to a summary of the telephone call released by the Trump administration on Wednesday.

Biden’s son Hunter worked for a Ukrainian gas company for several years.

A growing number of Democrats say the call was an abuse of Trump’s position and want to see him impeached. But the chances of the Republican president being removed from office look slim since his party controls the Senate where an impeachment trial would be held.

‘DEEPLY CONCERNED’

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The call occurred after Trump had ordered a freeze of nearly $400 million in American aid to Ukraine, which was only later released. Before the call, Ukraine’s government was told that interaction between Zelenskiy and Trump depended on whether the Ukrainian leader would “play ball,” the whistleblower said.

The report said Trump acted to advance his personal political interests, risking national security.

“I am deeply concerned that the actions described below constitute ‘a serious or flagrant problem, abuse, or violation of law or executive order,’” the whistleblower complaint, dated Aug. 12, said.

Pelosi said the fact that White House officials moved records of the call to another electronic system was evidence of a cover-up. “The president has been engaged in a cover-up all along,” she said.

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The Trump administration released the summary of the call after media reports about it surfaced.

The Ukraine controversy follows U.S. intelligence conclusions that Russia interfered in the 2016 U.S. election with a campaign of hacking and propaganda to boost Trump’s candidacy.

The whistleblower’s concerns did not end with Trump’s conversation with Zelenskiy. The next day, the report said, a U.S. special envoy for Ukraine negotiations and the U.S. ambassador to the European Union met with Zelenskiy and other Ukrainians and advised them “about how to ‘navigate’ the demands that the president had made of Mr Zelenskiy.”

Trump has repeatedly suggested wrongdoing by Biden and his son but has offered no evidence to back up the assertion. There has been no evidence that Biden used his position to help his son in the Ukraine matter.

Some of Trump’s fellow Republicans criticized the report. “Clearly a coordinated effort to take second-hand information to create a narrative damaging to the President,” Republican Senator Lindsey Graham said in a statement.

Trump has denied wrongdoing.

In the report, the whistleblower said that “I was not a direct witness to most of the events described” and based the account on information from colleagues.

During a House Intelligence Committee hearing, the top U.S. intelligence official, acting Director of National Intelligence Joseph Maguire, said the whistleblower had acted in good faith and followed the law in bringing the complaint.

Maguire frustrated committee Democrats when he declined to say whether he had discussed the whistleblower complaint with Trump. Maguire said it would not be “appropriate” for him to publicly rebuke Trump’s attacks on the whistleblower.

Maguire testified about the document after refusing for weeks to share it with Congress. Democrats said federal law required that the report be sent to lawmakers.

Schiff, the Democratic committee chairman, grilled Maguire about why the whistleblower report was withheld. Trump, Schiff said, “has betrayed his oath of office, betrayed his oath to defend our national security and betrayed his oath to defend the Constitution.”

Under the U.S. Constitution, the House has the power to impeach a president for “high crimes and misdemeanors.” No president has ever been removed through impeachment.