Oh my God... It is very terrify as people cannot should what they remember it really or fake, if what you are talking about is true. It is very unbelievable I think. If it is true, there existing some method to change people's memory....
Very horrible.
But in fact, maybe these people just forget what they have remember, not related to conspiracy?
You can try to google it, many different examples and stories. Yeah that may be true, but that's not a single person but thousands of people claiming the same thing.