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The Obama administration has confirmed that Hillary Clinton’s private server contained top secret emails, a revelation that deals a blow to her presidential campaign just days before the crucial Iowa caucuses.
More than 20 email exchanges are to be withheld from a scheduled release of email from Clinton’s time as secretary of state because they contain some of the government’s most closely guarded secrets, the Associated Press reported. So far, more than 1,300 of the Democratic presidential front-runner’s emails have been redacted, with portions blacked out to remove confidential information, according to the Wall Street Journal.
State Department spokesperson John Kirby said the agency will conduct an investigation to determine the security classification of the emails at the time they were sent. Some of the 1,000 emails scheduled for release Friday evening had been “upgraded” at the request of the intelligence community because they contain a category of top secret information, he said at a press briefing Friday.
“None of this traffic was marked classified at the time,” Kirby said in a press conference Friday.
The Clinton campaign issued a statement calling for the full release of the emails, which were first provided to the State Department a year ago.
“These emails were unmarked at the time they were sent, and have been called ‘innocuous’ by certain intelligence officials,” Clinton Press Secretary Brian Fallon said in a statement. “We understand that these emails were likely originated on the State Department’s unclassified system before they were ever shared with Secretary Clinton, and they have remained on the department’s unclassified system for years. And, in at least one case, the emails appear to involve information from a published news article.”
The latest disclosure regarding Clinton’s emails comes at a difficult time, on the eve of the Feb. 1 Iowa caucus vote, where she faces a tight challenge from Vermont Sen. Bernie Sanders. The emails have been problematic for Clinton since it was disclosed about 10 months ago that she used a private email server in her home while serving as secretary of state.
This article originally appeared on Recode.net.