Stories about a creature called the Ningen ( translates as “human like” I think) appeared on the internet in about 2007. It is said to be a whale like creature with a human face and some are reported to have arms. There are reports that these creatures like in the Antarctic Ocean. The reports say they are very pale or white and about 60feet (20metres) or larger in length. Sometimes they are called mermaid like .Supposedly reported being seen by crew members of government-operated whale research ships. One story says the crew members on deck saw what they thought was a submarine but when they got closer it was a live creature which disappeared under the water.
Large rays and some other flat fish can look as if they have a face on the underside and some grow very large. So speculation is that it could be a large flatfish like a ray floating upside down for whatever reason. It reminds me of H P Lovecraft’s Mountains of Madness story or that film The Abyss with the underwater alien. It could of course be a previously undiscovered species of Whale or elephant seal. Will wait and see if the first shaky photos appear.
See here for story and sighting : http://www.dailymotion.com/video/xfrmnu_alien-ningen-sighting-sagami-bay-japan-aug-23-2010_news