The declassified file 206-10001-10015 reveals a little-known internal CIA investigation from early 1964.
The target: a suspected mole inside the Agency who may have leaked internal surveillance methods to Soviet intelligence.
The trigger? A recording from a wiretap on a Cuban embassy line in New York that revealed knowledge the Agency assumed was classified.
The memo labeled the breach “Red-Level Internal Exposure.”
🎧 The Tape That Shouldn’t Have Existed
The CIA memo, dated February 12, 1964, describes a captured telephone conversation between two men speaking in Spanish.
One, presumed to be a Cuban national, casually refers to a specific U.S. audio surveillance configuration used to intercept conversations from a Cuban consulate office.
The line?
“Tell him to avoid the setup like in the 4th floor - they use the central drop under the air duct.”
According to the memo, that phrase exactly matched a method detailed in an internal CIA communications memo - distributed only to 12 people.
🔍 Internal Panic - And The Leak List
The moment the match was confirmed, a special review was ordered under Office of Security Case 4435-C, nicknamed “DEAD ECHO.”
The memo includes:
- A list of personnel who had access to the “central drop air duct” technique
- Notation that “6 of 12 persons reviewed have field experience with HT/LINGUAL and Cuban desk crossover”
- An urgent directive to monitor “off-hours communication logs”
👤 Suspected Profile: Language + Lateral Access
The mole theory took hold because the leak wasn’t just technical - it was linguistically specific. The memo notes that the speaker used phrasing identical to a training brief given to bilingual CIA surveillance officers.
“Phraseology suggests speaker either received CIA briefing or was briefed by someone with internal clearance.”
One side note even reads:
“No logical source for vocabulary outside direct agency exposure.”
🛑 But Then It All Stopped
The final page of the memo contains an abrupt closure note:
“Review suspended. Further inquiry deemed non-productive unless subsequent breach occurs.”
There’s no explanation.
No interviews.
No follow-up names.
Just an internal kill switch on the investigation - despite confirmation that someone, somewhere, leaked a surveillance method so specific it could only come from inside.
🧩 Was It Paranoia - Or Did The Mole Get Away?
What’s chilling is how quickly the mole hunt was abandoned.
📌 A known leak
📌 Matching language
📌 A cable marked RED LEVEL
📌 Twelve suspects
📌 Zero outcomes
The memo simply ends.
The 2025 release is the first public evidence that this mole hunt ever existed.
🧨 They Knew Someone Talked But They Chose Silence
In a world still reeling from Kennedy’s assassination, the idea of a breach within CIA walls was too explosive to pursue.
So instead - they shut it down.
And the speaker on the line?
Still unknown.