The message reads:
The result of investigation by FBI is so excellent that you might have seen what we were doing with your own eyes.
We congratulate you success.
FBI is the BEST in the world.
You will find the gift for FBI at the following address.”
They included a link to the following video titled “you are an idiot!”: https://www.youtube.com/watch?v=hiRacdl02w4
It appears that it is a link to a Japanese video that repeats the phrase "You are an idiot" in order to mock the FBI's investigation. There is speculation that this "You are an idiot" video is to criticize the FBI for blaming the Sony hack on North Korea. President Barack Obama this past Friday has already warned North Korea that the United States would respond to the cyber attack on Sony Pictures.