The Obama administration is confirming for the first time that Hillary Clinton's unsecured home server contained some closely guarded secrets, including material requiring one of the highest levels of classification.
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The revelation comes just three days before the Iowa presidential nominating caucuses in which Clinton is a candidate.
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The State Department will release more emails from Clinton's time as secretary of state later Friday.
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But The Associated Press has learned that 7 email chains are being withheld in full for containing "top secret" material.
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Department officials wouldn't describe the substance of the emails, or say if Clinton had sent any herself.
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Spokesman John Kirby tells the AP that no judgment on past classification was made. But the department is looking into that, too. (AP)
