FBI agent offers indirect evidence of leaks from ex-CIA man to reporter, but no smoking gun

The lead FBI agent on the case against an ex-CIA officer accused of leaking details of a classified mission to a journalist has acknowledged a lack of direct evidence proving the allegation.

Agent Ashley Hunt testified Wednesday in federal court in Alexandria as prosecutors conclude their case against Jeffrey Sterling of O'Fallon, Missouri.

Prosecutors say Sterling illegally told New York Times journalist James Risen about a purportedly botched operation to thwart Iran's nuclear ambitions because he was bitter over his treatment at the agency. Sterling denies the charge.

Hunt walked jurors through a series of phone and email records showing dozens of contacts between Sterling and Risen. But she admitted on cross-examination that she has no direct proof that the two talked about the classified operation.

Risen has refused to divulge his sources.