JUDY WOODRUFF, CNN ANCHOR: New details are emerging about the U.S. State Department laptop computer which disappeared in February and the magnitude of the highly-sensitive information held inside it. CNN's David Ensor joins us now with more -- David.</s>DAVID ENSOR, CNN NATIONAL SECURITY CORRESPONDENT: Judy, no secrets are more closely held by the intelligence community than sources and methods, the ways in which raw intelligence is gathered. It is top secret -- quote -- "code word" information. That could include anything from so-called signals intelligence, the methods used to eavesdrop on conversations among other nations' officials, to the identity of a U.S. spy. "We are talking," said one official, "about how we know things and how we keep track of things, and that information could help people take steps to avoid us knowing what they're up to." The missing laptop was used by State Department officials to log incidents of weapons proliferation. If, for example, there was information about an alleged sale of a Chinese or North Korean missile to, say, Iran it would be logged in along with the source of that information. Then, officials would screen out anything that might reveal sources and methods, and give American diplomats a bare-bones description that they could then use, for example, in a protest to Beijing. Investigators are interviewing every one with access to the secured room in question, from cleaning crews to diplomats. Officials say they are treating it as a possible case of espionage, but so far, Judy, they have no leads.</s>WOODRUFF: All right, David Ensor, thanks very much.
State Department Still Looking For Answers in Missing Laptop Investigation