The FBI and Justice Department engaged in improper and possibly illegal political spying by failing to disclose to a secret surveillance court that evidence used in targeting a Trump campaign adviser was funded by rival Hillary Clinton's campaign, according to an internal House memorandum made public Friday.

The memo revealed what it said were significant facts uncovered in an ongoing congressional probe of Russian election meddling that "raise concerns with the legitimacy and legality of certain [Justice Department] and FBI interactions with the Foreign Intelligence Surveillance Court."

The report concluded the improper spying represents "a troubling breakdown of legal processes established to protect the American people from abuses related to the FISA process." FISA is the Foreign Intelligence Surveillance Act that created a secret court and legal processes used in foreign spying probes.

The staff memo was released by the House Permanent Select Committee on Intelligence that in addition to investigating the 2016 election interference is investigating whether Obama administration officials abused intelligence reports by improperly unmasking the names of Americans incidentally captured in foreign surveillance.

In early 2017, several leaks of intelligence intercepts were disclosed in the press, including a conversation between Trump's national security adviser Michael Flynn and the Russian ambassador.

Release of the House memo followed several days of heated public debate in Congress and on social media, with Republicans urging disclosure and Democrats calling for the report to be kept secret in the interest of national security.

The four-page memo is sharply critical of senior FBI and Justice officials by name for signing off on misleading spying applications before the FISA court.

The officials failed to reveal evidence used in the spying request and renewals—the private intelligence dossier produced by former British intelligence officer Christopher Steele—was paid for by a law firm operating on behalf of the Clinton campaign and directed by the opposition research firm Fusion GPS.

The Washington Free Beacon employed Fusion GPS for political opposition research during the presidential primary campaign but had no involvement in the Steele dossier.

The foreign surveillance was carried out under four 90-day court orders beginning in October that called for surveilling Carter Page, a volunteer foreign policy adviser to Trump who the FBI suspected was a Russian spy.

Page, a former businessman in Russia, has denied any improper involvement with the Russians.

"The committee has discovered serious violations of the public trust, and the American people have a right to know when officials in crucial institutions are abusing their authority for political purposes," House Intelligence Committee Chairman Rep. Devin Nunes said in releasing the memo.

"Our intelligence and law enforcement agencies exist to defend the American people, not to be exploited to target one group on behalf of another."

President Trump called the abuses outlined in the memorandum "a disgrace."

Nunes said the committee's probe will shine light on "this alarming series of events" and added it could lead to reforms in FISA surveillance.

Nunes is also investigating whether senior Obama administration officials improperly obtained the identities of Trump advisers inadvertently caught in secret foreign intelligence surveillance.

The Obama officials include former White House National Security Adviser Susan Rice and former U.S. Ambassador to the United States Samantha Power who made an unusually large number of unmasking requests of the names of Americans in transcripts of intercepted conversations, congressional sources said.

The memorandum reveals deficiencies by senior FBI and Justice officials in handling the foreign spying court requests.

Improper FISA applications were signed by FBI Director James Comey, Deputy FBI Director Andrew McCabe, Deputy Attorney General Sally Yates, Acting Deputy Attorney General Dana Boente, and current Deputy Attorney General Rod Rosenstein, the memo states.

Comey and Yates were fired by Trump and McCabe resigned suddenly on Monday.

McCabe testified to the committee in December that without the now-discredited dossier "no surveillance warrant would have been sought" on Page, the memo says.

The memo states that when FISA warrants are requested for Americans, the government is required to provide the court with information potentially favorable to the targets. The requirement is designed to protect Americans' privacy rights.

"In the case of Carter Page, the government had at least four independent opportunities before the [FISA court] to accurately provide an accounting of the relevant facts," the memo says. "However, our findings indicate that material and relevant information was omitted."

The dossier by former British intelligence officer Christopher Steele has been the centerpiece of Democratic charges that Russia interfered in the 2016 election by colluding with the Trump campaign. So far the memorandum has not been verified and many parts of it were found to be false.

"Neither the initial application in October 2016, nor any of the renewals, disclose or reference the role of the DNC, Clinton campaign, or any party/campaign in funding Steele's efforts, even though the political origins of the Steele dossier were then known to senior DOJ and FBI officials," the memo said.

The initial FISA application also failed to mention that the FBI had separately authorized a payment to Steele for the same information contained in the private dossier.

Additionally, the FISA application used a Yahoo News story by Michael Isikoff to bolster its spying request on Page. But the application falsely stated the information in the news article did not come from Steele, the memo says.

Steele revealed in British court filings that he met with Yahoo News and other news outlets in September 2016 at the direction of Fusion GPS.

Also, after Steele was fired as an FBI source, he continued to provide information to then-Associate Attorney General Bruce Ohr, who worked closely with Yates and Rosenstein. Ohr was demoted as a result.

According to the memo, Ohr told FBI agents that Steele told him in September, two months before the election, that Steele "was desperate that Donald Trump not get elected and was passionate about him not being president," the memo said.

That information was never included in the FISA application and renewals.

Ohr's wife also worked for Fusion GPS and provided the FBI with her opposition research paid for by the DNC and Clinton campaign, the memo says.

The FBI's counterintelligence chief, Assistant Director Bill Priestap, said efforts to corroborate information in the Steele dossier were in an early stage at the time the FBI applied for the authority to spy on Page.

Steele was paid over $160,000 by the Democratic National Committee and Clinton campaign through the law firm Perkins Coie and Fusion GPS, an opposition research firm, the memo said.

Steele was dismissed as an FBI source after he was found to have lied to the FBI about contacts with news reporters.

The FBI later determined Steele's information was "only minimally corroborated." In January 2017, then-FBI chief Comey called the dossier "salacious and unverified."

The dossier, published in full by Buzzfeed, claimed that Trump engaged in kinky sex with prostitutes in Moscow.

The memo said the FISA request to spy on Page mentioned another Trump campaign adviser, George Papadopoulos, but there is no evidence of any cooperation or conspiracy between Page and Papadopoulos.

Papadopoulos pleaded guilty to lying to the FBI in October.

The information about Papadopoulos prompted the FBI to open a counterintelligence investigation in late July 2016 by FBI Pete Strzok.

Strzok was later found to have made a series of anti-Trump text messages with FBI attorney Lisa Page that revealed he was a Clinton supporter.

"The Strzok/Lisa Page texts also reflect extensive discussions about the investigation, orchestrating leaks to the media, and include a meeting with Deputy Director McCabe to discuss an ‘insurance' policy against President Trump's election," the memo says.

Trump said in a tweet: "The top Leadership and Investigators of the FBI and the Justice Department have politicized the sacred investigative process in favor of Democrats and against Republicans – something which would have been unthinkable just a short time ago. Rank & File are great people!"

Rep. Adam Schiff, ranking Democrat on the House intelligence committee, has been using information from the dossier for questions in committee hearing.

Schiff has said the American people do not have the underlying materials used in the committee memo and "therefore they can’t see how distorted and misleading this document is," he told CNN recently.

Committee Democrats declined to provide their dissenting views with the memo and instead sought to release a competing memo. That document is undergoing security review.

Congressional Democrats and many cable news pundits criticized the House Republicans in the days before the memo was released for endangering national security by releasing the memo

But the White House in a cover letter to the memo said the president and his legal and national security advisers determined releasing the memo is in the public interest.