SPYSCH_141026_680
Existing comment: When the Soviets checked on their underwater cable they saw the words "Property of US Government" written inside the bugging pod.

A Listening Bug in Enemy Waters:
In the early 1970s, the US government learned that the Soviet Union had constructed an undersea cable between two major naval bases. Although a network of sound detection devices protected the area, the Navy could not pass up the chance to intercept a goldmine of Soviet intelligence.
A team of combat divers worked with attack submarines to tap the undersea cable. They installed a tiny waterproof device that recorded all communications passing through the line. Every six to eight weeks, a submarine would return to collect the recording. This mission, Operation Ivy Bells, continued until its discovery by the Soviets in 1981.
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