NSA can retrieve, replay phone calls

America's National Security Agency has technology that is capable of recording the phone calls of an entire country and replaying them later, a report based on leaked documents said Tuesday. The Washington Post, citing papers released by the former NSA contractor Edward Snowden, said the eavesdropping agency's equipment functions like a time machine by being able to reach into the past.
The report said the NSA can collect 100 percent of the calls of a target country, reaching as far back as one month with tools called MYSTIC and RETRO. The leaked documents say the technology can "retrieve audio of interest that was not tasked at the time of the original call." A classified summary of the program cited by the Post said an NSA collection system can store billions of calls in a 30-day rolling buffer that clears the oldest calls as new ones arrive.