Hillary Clinton said today that she made the 'wrong choice' in using her personal email to conduct State Department business.

The Democratic presidential candidate said she does not, however, believe that she or anyone she was emailing with were 'careless' in their handling of classified information, as FBI Director James Comey stated at a press conference on Tuesday.

'I think that the professionals with whom I communicated were very careful about how they handled classified material as I was over the course of those for four years,' the former secretary of state told CNN's Wolf Blitzer today.

She said on MSNBC to Lester Holt, 'I do not believe that all of the professionals that I dealt with in the State Department were careless in handling classified material. I do not believe that they did anything that in any way they believed was inappropriate.'

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Hillary Clinton said today that she made the 'wrong choice' in using her personal email to conduct State Department business - but argued that she was not 'careless' and neither were here lieutenants

Clinton said she emailed with some 300 people in government during the time she served in the Obama administration, most of whom worked at the State Department or were in 'other high positions' in the federal government.

'They, I believe, did not believe they were sending any material that was classified,' she said on CNN this afternoon, speaking out about the Justice Department's investigation for the first time since the law enforcement agency said it would not bring charges in her email case.

Continuing, she told Blitzer, 'I do not think they were careless, and as I have said many times, I certainly did not believe that I received or sent any material that was classified.

'And indeed any of the.. documents that have been referred to, I think were not marked, were marked inaccurately, as has now been clarified.'

The former cabinet official has not said 'many times' that she did not 'believe' she received or sent classified information - she asserted repeatedly throughout the FBI's probe that it did not happen at all.

Comey said yesterday at a congressional hearing that the FBI found that on three occasions she was in fact sent information that bore classified markings, though the documents were did not have the proper heading.

The emails should have said they were classified in the heading, and they did not. Instead a 'C' for Confidential, the lowest classification level, appeared next to the sections the sender believed to contain classified information.

The State Department has since said that two of those emails should not have been marked Confidential at all.

The information in the emails was sensitive but unclassified and they were tagged improperly - something Clinton would have inherently known at the time, State Department spokesman John Kirby explained this week, based on the nature of the information.

Announcing the FBI's findings in its probe on Tuesday, before the State Department semi-absolved Clinton in two of the three instances in which she was found to have classified information in her inbox, Director Comey scolded the ex-secretary for running her emails through an unclassified personal server in her basement.

The FBI said 110 e-mails in 52 e-mail chains contained information that was classified at the time - even though they were not marked that way - and in eight instances the information was Top Secret, the highest level of classification.

'Even if information is not marked “classified” in an e-mail, participants who know or should know that the subject matter is classified are still obligated to protect it,' Comey said at the time.

He also stated at the news conference, which he says was not coordinated with the White House, the Attorney General Loretta Lynch or Clinton's presidential campaign that the bureau 'did not find clear evidence that Secretary Clinton or her colleagues intended to violate laws governing the handling of classified information.

'There is evidence that they were extremely careless in their handling of very sensitive, highly classified information,' he charged.

Today on CNN Blitzer prodded Clinton to say she and her lieutenants were as 'careless' as Comey said they were.

'I think the director clarified that comment to some extent, pointing out that some of what had been thought to be classified apparently was not. The State Department also made that clear,' she said.

Blitzer also brought up the 110 emails that were not marked classified but the originating agencies say contained highly sensitive information and should have been and asked Clinton if she personally 'should have known better.'

'I just believe that the material that was being communicated by professionals, many with years of handling sensitive classified material, they did not believe that it was,' she said, washing her hand of it again. 'I did not have a basis for second-guessing their conclusion.'

Clinton said she has the 'highest regard' for State Department staffers and told Blitzer, 'I have no reason to believe that they were careless in their judgments in sending me the material that they did.'

Cleared by the FBI and Justice Department this week, Clinton could still have to testify in a court case brought a conservative watchdog group trying to prove that she and her aides intentionally skirted the law by operating email addresses on the clintonemail.com domain.

The State Department also reopened its internal investigation into Clinton's email practices this week with the Justice Department probe now closed.

Clinton would not say today if she would cooperate with that review. She did not make herself available a State Department Inspector General assessment of her email practices.