The Snowden Files: The Paragraph began to delete itself.

[stevenleser]

3. If true, whoever did it should be fired from whatever agency was doing it for incompetence...

if nothing else.

If you have access to the OS to the point it seems whoever was doing this had access, its a simpler, or at least more covert matter to crash the OS and delete the file or revert it to a prior version.

An agent doing this ought to have worried that the person working on the article would whip out a smart phone and video what was happening.