FBI Director James Comey on Tuesday admonished Hillary Clinton for her “careless” use of private email servers during her tenure at the State Department, but said that she and her staff engaged in no “intentional misconduct” and should face no charges.

Noting that the FBI does not typically publicize its recommendations to Department of Justice prosecutors, Comey said at a surprise press conference that the high visibility of the probe required “unusual transparency.” He said his remarks were not coordinated with the Justice Department or “any other part of the government” and that they “do not know what I’m about to say.”

“Although there is evidence of potential violations of the statutes regarding the handling of classified information, our judgment is that no reasonable prosecutor would bring such a case,” he told the assembled journalists.

Attorney General Loretta Lynch said last week that she would “defer” to FBI investigators and career prosecutors on the case, after coming under fire for chatting with former President Bill Clinton during a run-in at a Phoenix, Arizona airport last week.

While Donald Trump and other prominent Republicans have said that Clinton should face criminal charges as a result of the probe, which grew out of the House Select Committee on Benghazi, federal officials maintained throughout the investigation that such charges were unlikely.

Comey emphasized, however, that Clinton and her staff were “extremely careless” with their handling of “very sensitive, highly classified information.” Emails containing information classified as secret by the U.S. intelligence community at the time they were sent and received were found on the private servers, which were unprotected.

The FBI director said there was “no evidence” that Clinton or her staffers “intentionally deleted” any of those emails in order to cover them up.

“Our assessment is that, like many e-mail users, secretary Clinton periodically deleted e-mails or e-mails were purged from her system when devices were changed,” Comey said.

Though the FBI director also said there was no “direct evidence” that “hostile actors” managed to hack into her email, he noted that it would be difficult to definitively confirm such covert hacking. Still, he said, hackers managed to gain access to the email accounts of people with whom Clinton corresponded from her personal account and she “extensively” used her personal account to discuss work-related issues while “in the territory of sophisticated adversaries.”

As a result, Comey said, “we assess it as possible that hostile actors gained access to secretary Clinton’s personal e-mail account.”

He revealed that the exhaustive investigation was complicated by the fact that Clinton used “several different servers” and “numerous mobile devices” during her four-year tenure as secretary of state.

The FBI combed through 30,000 emails provided by Clinton to the State Department in 2014, and dug up several thousand additional work-related emails not included in this mass turnover. The agency also interviewed top members of her staff and, on Saturday, conducted a three-hour long voluntary interview with the Democratic presidential candidate about her email use.

The lawyers who helped Clinton sort through her email system to produce the 30,000 emails sent to the department were also cleared of wrongdoing.

“We believe our investigation has been sufficient to give us reasonable confidence there was no intentional misconduct in connection with that sorting effort,” Comey said.

The FBI director took no questions from the press and quickly left the room after completing the fifteen-minute briefing.

The email imbroglio has dogged Clinton and her presidential campaign for years. While Comey’s announcement likely takes charges off the table, Republicans found plenty of political fodder to take away from his presser. Trump sent a tweet calling the FBI’s conclusion proof that “the system is rigged.”

The system is rigged. General Petraeus got in trouble for far less. Very very unfair! As usual, bad judgment. — Donald J. Trump (@realDonaldTrump) July 5, 2016

The announcement came the same day that President Barack Obama was expected to join Clinton on the campaign trail in their first joint appearance since he endorsed her in June.

This post has been updated.