Number stations are radio broadcasts that continuously transmit weird stuff like rhythmic buzzing, numbers, music, etc. Allegedly, they are used to transmit coded messages to spies around the world. The spies tune into the broadcast at certain time on a certain date, and using a one-time pad, the spies decode the message. There was even a movie about these number stations starring John Cusack.
Anyway, a youtuber recorded a string of numbers transmitted by one of these number station. He was allegedly able to crack the transmission using a Commodore 64. One of the comments in the youtube video took it further and was able to fully decode the message. The message, which I don't feel comfortable repeating, was about a very important naval vessel's movements.
The youtuber who ran the channel had about 28,000 subscribers and tens of millions of views. After this message was cracked, decoded, and posted in the comments, the video was deleted. Furthermore, all traces, mirrors, and copies of the video posted on other platforms were erased. EVEN FURTHER, the youtuber's ENTIRE YOUTUBE CHANNEL WAS REMOVED. No one knows what happened, but it's assumed that the decoded message was correct. I learned about this in another subreddit, which is not private but shall remain nameless.
This is all speculation. Please don't assassinate me.