108. Telegram From the Embassy in the Soviet Union to the Department of State1

11770. Subject: Technical Penetration of US Embassy Moscow. Ref: (A) Moscow 11684, (B) Moscow 11713 (C) Moscow 11720.2

1. We have entered and explored tunnel. It heads about 25 feet due north then makes a gradual left turn and further progress is blocked [Page 351] about 40 feet further on by a sheet metal barrier. Barrier appears to definitely be off the Embassy compound.

2. There are four cables exiting the chimney that head down the tunnel. One services the antenna, two go into the back of the line box mentioned in reftel C, and one connects to a Uher microphone with a switch encased in a plastic bag. All four cables terminate in a jumble of cable located about two feet in front of the sheet metal.

3. About ten feet beyond the bend three heavy black cables enter what appears to be the basement of the Soviet apartment building. These cables continue down the tunnel and enter the jumble in front of the sheet metal.

4. Two heavy black cables exit the jumble and go through the roof of the tunnel.

5. Tunnel ceiling turns from brick to sheet steel beyond point where three cables enter building basement.

6. Small opening (two foot square) is located to the south just in front of sheet metal barrier. This opening is blocked off by loose brick.

7. There appears to be five trip wires connected to the loose brick fill. These wires are soldered to heavier gauge wires that either enter the wire jumble or a plastic wrapped object about the size of a transistor radio.

8. Two tunnel accesses are in the Soviet changing room as reported in reftel C.

9. We are now trying to trace all cables without disturbing trip wires.

10. Since opposition will definitely be alerted at 8:00 a.m. when Soviet workers will be denied access to changing room, we request immediate Departmental guidance.

11. Once opposition is alerted, we suspect they will enter tunnel from the far end and seal off access or remove as much cabling as possible.

12. Photographic documentation continues.

Matlock
  1. Source: Carter Library, National Security Affairs, Staff Material, Office, Unfiled Files, Box 152, USSR: Technical Penetration of US Embassy in Moscow: 5–6/78. Secret; Niact Immediate. Sent via the SY Channel.
  2. See Document 106 and footnote 2 thereto and Document 107.