Silently, under the cover of darkness, the national headquarters of the CIA vanished Tuesday, leaving no sign that it had ever been there at all. The multibuilding campus of the intelligence-gathering agency reportedly disappeared without warning, taking with it all occupants and leaving in its place 258 acres of peaceful woodland. 'I don't know what you're referring to,' National Intelligence Director Dennis C. Blair said. 'I've never heard of this headquarters or the agency it supposedly housed. There's no story here.' An anonymous source claimed to have more information on the incident, but a reporter dispatched to meet him in a Langley, VA parking garage found the facility empty, and left having only heard a few dull thuds and the squealing of tires. 