The Justice Department’s top watchdog blasted the FBI for a series of “fundamental errors” in its probe of a Trump campaign official but said it found no evidence that political bias fueled the investigation.

Less than an hour after the long-awaited findings from Inspector General Michael Horowitz were released, a federal prosecutor conducting a separate investigation of the FBI’s action—and reporting directly to Attorney General Bill Barr—pushed back.

“Our investigation is not limited to developing information from within component parts of the Justice Department,” John Durham, the U.S. attorney in Connecticut, said in response to Horowitz’s report.

“Our investigation has included developing information from other persons and entities, both in the U.S. and outside of the U.S. Based on the evidence collected to date, and while our investigation is ongoing, last month we 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.”

Although Horowitz, in his report, concluded that the FBI had sufficient evidence to launch its counterintelligence probe of Trump associates, he also cited “at least 17 significant errors or omissions” in the FBI’s applications to surveil ex-Trump adviser Carter Page.

The problems with the efforts to secure authorization were so concerning that Horowitz is opening a new audit looking at how the FBI obtains authorizations from the secretive Foreign Intelligence Surveillance Court to surveil Americans.

“That so many basic and fundamental errors were made by three separate, hand-picked teams on one of the most sensitive FBI investigations that was briefed to the highest levels within the FBI, and that FBI officials expected would eventually be subjected to close scrutiny, raised significant questions regarding the FBI chain of command’s management,” the report said.

The report also found that a confidential human source working for the FBI recorded a conversation with a high-level Trump campaign official during the election season. That official “was not a subject of the investigation,” the report noted.

The report also said that the inspector found no “documentary or testimonial evidence that political bias or improper motivation” influenced FBI decisions to open investigations of Trump campaign associates, to use confidential sources interact with them, and to seek authority to surveil Page.

Still, Horowitz’s findings about the Carter Page surveillance authorization will likely cheer Trump and his allies, who have long argued that the FBI abused its power in investigating people linked to his 2016 presidential campaign. Attorney General Bill Barr praised the investigation but appeared to dispute one of its conclusions.

“The Inspector General’s report now makes clear that the FBI launched an intrusive investigation of a U.S. presidential campaign on the thinnest of suspicions that, in my view, were insufficient to justify the steps taken,” the attorney general said in a statement. “It is also clear that, from its inception, the evidence produced by the investigation was consistently exculpatory. Nevertheless, the investigation and surveillance was pushed forward for the duration of the campaign and deep into President Trump’s administration.”

An attorney for former FBI Director Andrew McCabe said his client was unaware of the problems cited by Horowitz in the report.

“Mr. McCabe did not know about any of these issues and the report makes clear that there is no way he could have known unless someone specifically brought them to his attention,” lawyer Michael Bromwich said. “The report makes clear that no one did.”

Horowitz announced on March 28, 2018, that he was launching a review to scrutinize DOJ and FBI compliance with legal and procedural requirements when seeking authorization to surveil “a certain U.S. person.” His announcement also said he would scrutinize the FBI’s relationship with an “alleged source.”

The U.S. person is known to be Page, who served as a foreign policy advisor to the Trump campaign for a brief period. The surveillance began after he parted ways with the campaign. And the alleged source is Christopher Steele, a former British intelligence officer who wrote a series of memos during the 2016 campaign about relationships between denizens of Trump World and Russian nationals. The Democratic National Committee and Hillary Clinton’s campaign paid for Steele’s work through the research firm Fusion GPS.

The review generated fervid speculation from the president’s allies over the last 18 months, many of whom predicted the final report would show gross wrongdoing by the bureau.

Earlier this year, Barr told a congressional committee that he believed the Intelligence Community may have spied on the Trump campaign.

“I think spying on a political campaign is a big deal,” he said. “It’s a big deal.”

“I’m not suggesting that those rules were violated,” he continued, “but I think it’s important to look at that. I’m not talking about the FBI necessarily but intelligence agencies more broadly.”

The comments left American intelligence officials distressed, as Barr appeared to be co-signing Trump’s claims that he was the victim of gross wrongdoing during the 2016 campaign.

The FBI began a counterintelligence investigation that included Trump World figures after an Australian diplomat alerted the FBI to a conversation he had with George Papadopoulos. Papadopoulos, who had advised the campaign on foreign policy, had told the diplomat that the Kremlin had dirt on Hillary Clinton.

Later in 2016, the FBI scrutinized Page, who at that point had departed Trump’s foreign policy team. Page had close connections with Russian nationals, and a federal court authorized the Justice Department to surveil his communications.

That surveillance continued after Election Day and into the Trump administration. When seeking authorization to surveil Page, DOJ officials cited information from the Steele Dossier. Republicans have argued that the applications did not clearly state the source of that information, and that the surveillance of Page was a set-up.

Special Counsel Robert Mueller took over that counterintelligence investigation in May 2017. His probe investigated Kremlin interference in the 2016 election and resulted in a host of indictments and convictions—including of Papadopoulos, who pleaded guilty to lying to the FBI and served a short prison sentence. Papadopoulos has since become a folk hero on the right.

Horowitz said in his report that he examined an allegation by Papadopoulos that the FBI used Maltese university professor Joseph Mifsud to pass information to him as a pretext for opening the Trumpworld probe. The IG said he could find no witnesses or documents to support that.

In his own statement, Barr noted that Horowitz found “the only information relied on to open the FBI’s counter-intelligence investigation was supplied to the FBI by a friendly foreign government”—the Australian diplomat.

Barr said the diplomat did the right thing, but added, “What was subsequently done with that information by the FBI presents a separate question.”