Bradley Klapper

WASHINGTON: The Obama administration confirmed for the first time Friday that Hillary Clinton’s home server contained closely guarded government secrets, censoring 22 emails that contained material requiring one of the highest levels of classification. The revelation comes three days before Clinton competes in the Iowa presidential caucuses.

State Department officials also said the agency’s Diplomatic Security and Intelligence and Research bureaus are investigating if any of the information was classified at the time of transmission, going to the heart of Clinton’s defense of her email practices.

The department published its latest batch of emails from her time as secretary of state Friday evening.

But the Associated Press learned ahead of the release that seven email chains would be withheld in full for containing “top secret” information. The 37 pages include messages a key intelligence official recently said concerned “special access programs” — highly restricted, classified material that could point to confidential sources or clandestine programs like drone strikes.

“The documents are being upgraded at the request of the intelligence community because they contain a category of top secret information,” State Department spokesman John Kirby told the AP, calling the withholding of documents in full “not unusual.” That means they won’t be published online with others being released, even with blacked-out boxes.

Department officials wouldn’t describe the substance of the emails, or say if Clinton sent any herself.

Clinton, the Democratic presidential front-runner, insists she never sent or received information on her personal email account that was classified at the time.

No emails released so far were marked classified, but reviewers previously designated more than 1,000 messages at lower classification levels. Friday’s will be the first at top secret level.

Even if Clinton didn’t write or forward the messages, she still would have been required to report any classification slippages she recognized in emails she received. But without classification markings, that may have been difficult, especially if the information was publicly available.

“We firmly oppose the complete blocking of the release of these emails,” Clinton campaign spokesman Brain Fallon said. “Since first providing her emails to the State Department more than one year ago, Hillary Clinton has urged that they be made available to the public. We feel no differently today.”