Most countries, in general, keep their UFO reports private. This would also include USOs or Unidentified Submersible Objects. Some countries such as China and Russia release almost nothing. Their veil of secrecy in some ways matches that of the United States government. However, recently we have seen more information coming out of Russia and most of it has to do with USOs. Now we have come across a Russian documentary focused on these underwater objects which fortunately has subtitles and you can check it out below.