'Deep Throat' remains a deep secret

'I'm close, in fact very close,' says former White House aide

Former White House aide John Dean

(CNN) -- Thirty years later, the secret is still as tightly sealed as an entombed coffin.

Despite a promise from former White House counsel John Dean, Watergate wonderers did not learn Monday the identity of Deep Throat, the secret source who directed Washington Post reporters in their investigation of the notorious 1972 break-in at the Democratic National Committee headquarters.

Dean, an aide to former President Richard Nixon -- whose administration was brought down by the Watergate scandal -- authored an e-book and promised to name Deep Throat on Monday, the 30th anniversary of the burglary. The secret was to be revealed in the online magazine Salon.com.

CNN NewsPass VIDEO Thirty years after the Watergate scandal, CNN's Anne McDermott looks into the mystery of the informant known as 'Deep Throat' (June 17) Play video   MORE STORIES Just who is Deep Throat?    EXTRA INFORMATION Gallery: Watergate: the key players    WATCH CNN TV Carl Bernstein talks to CNN's Aaron Brown Monday, 10 p.m. ET.    Deep Throat According to Bob Woodward Is one individual Is a man Is still alive Held an extremely sensitive position in the executive branch As of 1972, Deep Throat was a smoker and was fond of Scotch Before the term Deep Throat was coined, Woodward referred to him as an "old friend"

But it isn't happening, and the reporters who could point the finger have vowed to keep the secret until Deep Throat dies.

Dean spent 127 days in prison for his role in the Watergate scandal and testified before the Senate about Nixon's involvement in covering up the break-in. He's spent parts of the last 25 years researching the identity of Deep Throat.

He's had a number of theories, naming Watergate prosecutor Earl J. Silbert and Nixon's chief of staff, Alexander M. Haig, as potential candidates. Both have denied being Deep Throat.

As publication of the e-book neared, denials became stronger and Dean and Salon.com backed away from naming names.

In the book's preface, Dean writes: "On June 17, 2002, the 30th anniversary milestone of the Watergate break-in, I had planned to publish the name of the person I believed was Washington Post reporter Bob Woodward's source, Deep Throat, and explain the reasons for my conclusion in considerable detail. As set forth in the following pages, I will not complete my work at that time. But I'm close, in fact very close...

"Because of the surprisingly widespread interest in this suspenseful topic, and not wishing to add any more suspense by reason of my own efforts, I'm publishing what might be considered an interim report -- where I am, and how I got there -- and providing what I believe are all the known clues and key information about Deep Throat for all those interested.

"I've found that Deep Throat sleuthing has become increasingly tricky and unpredictable, as the field narrowed. So rather than allow a self-imposed deadline to limit my research, I will simply continue my pursuit, and work to conclude it as quickly as possible."

Watergate fans can purchase the e-book for $8 at Salon.com.