WASHINGTON (CBSNewYork/AP) -- The Obama administration confirmed for the first time Friday that Hillary Clinton's unsecured home server contained closely guarded government secrets, censoring 22 emails with material requiring one of the highest levels of classification.
As CBS2's Dick Brennan reported, the bombshell revelation came just three days before the Iowa presidential nominating caucuses in which Clinton is a candidate.
Department officials also said the agency's Diplomatic Security and Intelligence and Research bureaus will investigate whether any of the information was classified at the time of transmission, going to the heart of one of Clinton's primary defenses of her email practices.
The State Department said seven email chains from Clinton's private account, totaling 37 pages, were being upgraded to top secret.
"In consultation with the intelligence community, we are making this upgrade and we believe it's the prudent, responsible thing to do," said State Department spokesman John Kirby.
"Top secret" is one of the highest levels of classification, reserved for materials that if released would cause "exceptionally grave damage to national security."
Department officials wouldn't describe the substance of the emails, or say if Clinton sent any herself.
The emails from Clinton's years as secretary of state were on her private server in her home in Chappaqua, until she turned over 55,000 pages at the department's request.
Clinton, the front-runner for the Democratic presidential nomination, has insisted she never sent or received information on her personal email account that was classified at the time. No emails released so far were stamped "CLASSIFIED" or "TOP SECRET," but reviewers previously had designated more than 1,000 messages at lower classification levels for public release. Friday's will be the first at the top secret level.
Even if Clinton only read, and didn't write or forward the secret messages, she still would have been required to report classification slippages that she recognized. But without classification markings, that may have been difficult, especially if the information was in the public domain.
Clinton's campaign called the move overclassification run amok," and Friday night on NBC, Clinton said she did nothing wrong.
"The facts have remained the same," she said. "There was never any information sent or received that was marked classified to me,"
Kirby said the State Department was focused, as part of the Freedom of Information Act review of Clinton's emails, on "whether they need to be classified today." Questions about their past classification, he said, "are being, and will be, handled separately by the State Department."
Possible department responses for classification infractions include counseling, warnings or other action, State Department officials said, though they declined to say if these applied to Clinton or senior aides who've since left the department. The officials weren't authorized to speak on the matter and spoke on condition of anonymity.
Separately, Kirby said the department also was withholding eight email chains, totaling 18 messages, between President Barack Obama and Clinton. These are remaining confidential "to protect the president's ability to receive unvarnished advice and counsel," but will ultimately be released like other presidential records.
Friday's release is coming at an awkward time for Clinton. The Iowa caucus is on Feb. 1, and her main challenger, Vermont Sen. Bernie Sanders, is running a competitive campaign in Iowa and New Hampshire. Clinton still holds a strong advantage in national polls.
The emails have been an issue for Clinton's campaign since it became known 10 months ago that she exclusively used a non-government account linked to a homebrew server while in office. Clinton first called the decision a matter of convenience and then termed it a mistake, even if doing so wasn't expressly forbidden. But the matter could prove more troublesome now that Clinton's former agency has confirmed that business conducted over the account included top-secret matters.
Like Clinton, the State Department discounted such a possibility last March. Both also said her account was never hacked or compromised. Security experts assess that as unlikely, and that the vast majority of her emails were preserved properly for archiving purposes because she corresponded mainly with government accounts. They've backtracked from the archiving claim, while the AP discovered several phishing attempts on her server connected to Russia.
The question of special access programs first surfaced last week, when Charles I. McCullough, the inspector general for U.S. intelligence agencies, cited examples on Clinton's account in a letter to Congress. Republicans pounced on the report, though Clinton's campaign insisted none of the exchanges were "classified at the time" and accused McCullough and GOP lawmakers of selectively leaking materials to damage her presidential hopes.
Kirby confirmed that the "denied-in-full emails" are among those McCullough recently cited. One of the emails, he said, was among those McCullough identified last summer as possibly containing top secret information.
The AP reported last August that one focused on a forwarded news article about the classified U.S. drone program run by the CIA. Such operations are widely discussed in the public sphere, including by top U.S. officials, and the State Department immediately argued with McCullough's claim. The other concerned North Korean nuclear weapons programs, according to officials.
At the time, several officials from different agencies suggested the disagreement over the drone emails reflected the government's tendency to overclassify material, and the lack of consistent policies across difference agencies about what should and shouldn't be classified.
The FBI also is looking into Clinton's email setup, but has said nothing about the nature of its probe. Independent experts say it is highly unlikely that Clinton will be charged with wrongdoing, based on the limited details that have surfaced up to now and the lack of indications that she intended to break any laws.
"What I would hope comes out of all of this is a bit of humility" and an acknowledgement from Clinton that "I made some serious mistakes," said Bradley Moss, a Washington lawyer who regularly handles security clearance matters.
Legal questions aside, it's the potential political costs that are probably of more immediate concern for Clinton. She has struggled in surveys measuring her perceived trustworthiness and an active federal investigation, especially one buoyed by evidence that top secret material coursed through her account, could negate one of her main selling points for becoming commander in chief: Her national security resume.
Meanwhile on the Republican side Friday, Donald Trump said he had no regrets about skipping the Republican presidential debate in Iowa Thursday night to host a fundraiser for veterans.
Trump spoke about it with "Face the Nation" anchor John Dickerson.
"We gave a tremendous performance with lots of different people for the veterans," he said. "We got great coverage, because the debate was not as exciting as what we did."
Trump said he raised $6 million for veterans at the event. More of his interview with Dickerson can be seen Sunday on "Face the Nation."
(TM and © Copyright 2016 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2016 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)
for more features.