If you had suspicion of moles in your organization, wouldn't you at least want to investigate the matter further? Well that is just not the way the FBI does things, according to this story from a busy blogger:
When she alerted her superiors and the special agent in charge of the investigation about what she found, no one wanted to hear about it. Shortly thereafter, not only was she fired, "her home computer was seized; her family in Turkey was visited by police and threatened with arrest if they did not submit to questioning about an unspecified 'intelligence matter.'"Read the whole thing.
The FBI never gave an explanation for her firing, but three months later admitted that Ms. Edmonds had been correct and... [her] valid complaints were a contributing factor to her dismissal.