FBI Director James Comey said Tuesday that his agency would not recommend criminal charges against anyone involved with Hillary Clinton's private email network, even after finding that Clinton's team was "extremely careless" in handling classified emails.

"We cannot find a case that would support bringing criminal charges," he told reporters in Washington. Comey added that "no reasonable prosecutor" would bring charges.

Still, he said Clinton sent or received dozens of emails that were classified at the time they were sent and noted the former secretary of state did not turn over thousands of work-related emails to the State Department.

Comey said 110 emails contained information that was classified at the time they were sent, including eight emails that were top secret. That finding marked a direct contradiction to Clinton's previous statements, in which she said she never sent any information that was classified at the time it was sent.

Comey said the investigation focused on whether Clinton violated federal statutes prohibiting the removal of classified information from secure areas, which is a crime whether that is done intentionally or inadvertently.

The FBI director said Clinton used several different servers and mobile devices to transmit her private emails, a previously unknown detail about her network, and said it is "possible" that her inbox was breached by hackers.

Comey described the effort to comb through Clinton's multiple servers and devices as "a painstaking undertaking requiring thousands of hours of effort."

The FBI does not ordinarily announce its recommendations to career prosecutors at the Justice Department, Comey said, but he cited the "importance" of the case while explaining his decision to hold a press conference Tuesday.

Attorney General Loretta Lynch announced Friday her intention to rely on the recommendation given to her by the FBI amid an intense backlash over her private meeting with Bill Clinton earlier last week. That means Lynch is now likely, as expected, not to pursue charges against Clinton.

Comey has repeatedly vowed to prevent political bias from affecting the Clinton email investigation, but has otherwise refused to address the probe publicly since it began in July 2015.

While Hillary Clinton continues to characterize the investigation as a routine "security review," Comey, the White House and a federal judge have acknowledged that the probe is criminal in nature.

Republicans have long accused the Obama administration of attempting to rein in the FBI's investigation, from the president's dismissal of the probe in October of last year to Lynch's refusal to name a special prosecutor to the case.