WASHINGTON, March 4 (Xinhuanet) -- The U.S. government has adopted a series of initiatives to discourage government employees from leaking classified information to journalists, The Washington Post reported in its Sunday edition.

    The efforts include several FBI probes, a polygraph investigation inside the CIA and a warning from the Justice Department that reporters could be prosecuted under espionage laws, the Post said.

    FBI agents have interviewed dozens of employees at the CIA, the National Security Agency (NSA) and other intelligence agencies in recent weeks as they investigate possible leaks that led to reports about secret CIA prisons in Eastern Europe and the NSA'sdomestic surveillance program, the paper said. 

    Numerous employees at the CIA, FBI, the Justice Department and other agencies also have received letters from the Justice Department

    prohibiting them from discussing even unclassified NSA program,the Post said, citing sources familiar with the notices. 

    FBI agents from Los Angeles have already contacted reporters atthe Sacramento Bee about their coverage of a terrorism case that was based on classified court documents, the Post said.

    At Langley, the CIA's security office has been conducting numerous interviews and polygraph examinations of government employees in an effort to discover whether any of them have had unauthorized contacts with reporters, the Post said.  

    Some media watchers, lawyers and editors told the Post the incidents perhaps represent the most extensive anti-leak campaign in a generation and that they have worsened the already tense relations between mainstream news organizations and the White House.  Enditem