The mainstream news organisations carefully selected cables and before publication removed any information which could lead to sensitive sources being identified.

One of the first things a professional intelligence officer learns is that sensitive sources and methods cause material to be compartmented.

He added that information in his statements on the House floor "in no way harmed the national security or revealed sensitive sources and methods."

But they also offer information not obtainable by reporters pressed to publish every day, who have to worry about maintaining relationships with sensitive sources.

But ever since, objections by the intelligence community over the potential disclosure of sensitive sources prevented any detailed public release of information.

They allow for the protection of sensitive sources, and methods of intelligence gathering.

A very sensitive source, probably a spy rather than an intercept.

Intelligence is taken from such extremely sensitive sources that it cannot be used without exposing the methods or persons providing such intelligence.

Because the information about tampering came from a highly sensitive source, no announcement was made at the time and the trial was allowed to proceed.

Our report is classified top secret because the F.B.I., not my office, deems much of the information to reveal sensitive sources and methods.