The source said the investigation is centered around 18 US Code 793, a section of the Espionage Act related to gathering and transmitting national-defense information.
Two emails reportedly found on Clinton's server from 2009 and 2011 contained information regarded as "Top Secret/Sensitive Compartmented Information," one of the highest levels of classification.
The two emails were drawn out of a batch of 40 randomly selected from about 30,000 "work-related" emails that Clinton turned over to the State Department from her time as secretary of state, from 2009 to 2013
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