Actually, I think Operation Gladio is a great example of something that could have very conceivably meet your criteria. Gladio is NATO's oldest covert mission. It was also one of the first missions that CIA cooperated on -- the CIA having largely been started to throw the free elections in Post-WWII Italy.
Gladio was a Stay-behind operation. That means that it was a fall-back. It's an ambitious plan B that involved installing covert agents by way of natural (ideally) elevation and promotion so in the event of a regime change they have already established trust within the new regime to carry out the initiative.
The only questions are (1) how did Gladio operatives receive their instructions and (2) what would those instructions have looked like?
To answer the second question, it's quite clear Gladio was an operation of death, terrorism, assassination and infiltration. Just read about the operation in Italy. There were 127 weapons caches the Italians had to dismantle from this operation.
And, on to the first question.. Who really cares? It's logical with a weapon cache in another country the action would have had to be triggered remotely on the command of whomever set up or participated in the secret op. Did the trigger come by way of a mass communication? It'd have been more conceivable in 1950's with a mission the size of Gladio, but I don't have any evidence that it was so. Now with SSL and IPSEC it's highly unlikely to permit the message to traverse an unsecured medium. If such an operation ever happened with mass media used in the trigger you should be reading about the years of 1900-1975.