WASHINGTON — President Donald Trump said Monday that a new Justice Department report that found a solid legal basis for the original FBI investigation of his 2016 campaign had actually documented an "attempted overthrow" of the government that was "far worse than I ever thought possible.

"It is an embarrassment to our country, it is dishonest, it is everything that a lot of people thought it would be except far worse," he said at the White House, following the release of the long-awaited report by the Justice Department's watchdog that rebutted his regular depiction of a politically biased plot against him.

While the report by Justice Department Inspector General Michael Horowitz rebutted Trump's repeated claim that his campaign was spied on by the FBI as part of a politically motivated "witch hunt," Trump and his allies looked to focus on investigator missteps documented in the report.

The report concluded that the FBI and the Justice Department launched their investigation into the 2016 campaign not for political reasons, but due to evidence the Russian government was using go-betweens to reach out to the Trump campaign as part of its efforts to influence the election.

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But Trump sought to shift focus to the report's findingthat the FBI mishandled parts of its application to monitor a former Trump campaign aide as it probed possible Russian interference in the 2016 election, rather than focusing on the conclusion that the overall investigation was justified and not politically motivated.

"It is a disgrace what has happened with respect to the things that were done to our country. It should never again happen," said Trump, adding the findings were "far worse than I would have ever thought possible."

Horowitz and his team spent nearly two years on an investigation that was intended to scrutinize the FBI's surveillance of Carter Page, a foreign policy adviser to the Trump campaign who had traveled to Russia and had previously been the target of recruitment by Russian intelligence officers.

The report said the surveillance of Page, which began in October 2016, did not spark the FBI's Russia investigation, which began in July 2016 after an Australian diplomat reported that a different Trump aide had learned from a Russian agent that the Russian government possessed thousands of Democratic emails.

Perhaps the most concrete example of apparent misconduct the inspector general uncovered concerns what he says was the altering of an email regarding Page's relationship as a source to an unnamed government agency. An FBI lawyer altered the email, the report says, in a way that hid the fact that Page had been a source. That information would have been relevant to the court, the report says, in the context of Page's dealings with Russians.

"We found that the FBI did not have information corroborating the specific allegations against Carter Page in Steele's reporting when it relied upon his reports in the first (warrant) application or subsequent renewal applications," the report said.

Trump campaign manager Brad Parscale echoed the president Monday, saying the report “confirms significant misconduct and wrongdoing by the Obama-Biden FBI" and that "politically motivated accusations were used to justify the surveillance of a U.S. presidential campaign by the FBI, which falsified information and concealed evidence that didn’t fit their narrative."

Just months into his presidency. Trump claimed that President Barack Obama had his phones lines tapped in Trump Tower, a claim he said earlier this year "turned out to be true," despite no evidence of any such action. The report released Monday said that was not the case.

Before it was made public, Trump had looked to promote it over the impeachment hearings taking place the same day.

"I.G. report out tomorrow. That will be the big story!" he tweeted Sunday.

Trump has also been seeking to shift the focus to another report being carried out by the U.S. attorney for Connecticut, John H. Durham, who was appointed by the attorney general to look into the origins of the investigation.

In an unusual move for an investigator who has yet to conclude his work, Durham said in a statement Monday that he had "advised the Inspector General that we do not agree with some of the report’s conclusions as to predication and how the FBI case was opened.”