The National Security Agency has technology capable of recording all the phone calls of an entire country and replaying them later, a report based on leaked documents said Tuesday.

The Washington Post, citing documents leaked by former NSA contractor Edward Snowden, said the technology 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 country and reach as far back as one month with the tools called MYSTIC and RETRO....