The plea agreement calls for 140 months in prison for both crimes.
A law enforcement official speaking on condition of anonymity said the pornography investigation helped identify Sachtleben as a suspect in the leaks case. The official would not be named because of the Justice Department policy against identifying innocent parties.
The department seized AP phone records in its search for the information's source.
AP spokesman Paul Colford said, "The AP never comments on its sources."
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