The FBI is investigating the White House, the Pentagon, the NSA, the CIA and other intelligence agencies.
They are hunting for sources that, according to the New York Times, leaked to the media information on the Stuxnet cyber attack in Iran, a foiled terrorist plot in Yemen, and the "kill list"—a once-secret list of suspected terrorists marked for drone strikes.
Consequently, the media's ability to cover national security has been hindered, as agencies turn down basic interview requests and decline to provide background briefings, according to the New York Times.
“People are being cautious,” one intelligence official told the New York Times. “We’re not doing some of the routine things we usually do.”
Gregg Leslie of the advocacy group Reporters Committee for Freedom of the Press, said, “Reporters are beginning to resort to the old practice of meeting on a park bench to avoid leaving an electronic trail.”
The series of recent leaks prompted legislators to design an anti-leaking bill that could limit intelligence officials’ contact with reporters.
If made a law, some measures adopted would be:
• A requirement to notify Congress when intelligence information is disclosed to the public (outside of the FOIA or the regular declassification review process) and to maintain a record of all authorized disclosures of classified information
• A requirement to establish formal procedures for leak investigations
• A requirement to assess procedures for detecting leaks, including expanded use of polygraph testing in other parts of the executive branch
• A prohibition on cleared personnel (or formerly cleared personnel for up to a year after employment) serving as paid consultants or commentators to a media organization regarding intelligence matters
• A requirement that only certain designated intelligence community officials may communicate with the media
Committee Chair Sen. Dianne Feinstein said in a news release, "Leaks of classified information regarding intelligence sources and methods can disrupt intelligence operations, threaten the lives of intelligence officers and assets, and make foreign partners less likely to work with us. The culture of leaks has to change."
Here's an ABC report explaining what the foiled terrorist plot in Yemen and the subsequent leak were all about.
If you don't know what the "kill list" is, here's an explainer from PBS and Scott Shane of the New York Times: