I guess the correct term here would be USO (Unidentified Submersible Object). The story comes from Ben Radford over at MSNBC with the title:

UFO found on ocean floor?

Swedish explorer reports circular anomaly, but is it a ‘flying saucer’? Hardly

According to an ocean exploration team led by Swedish researcher Peter Lindberg, their sonar equipment captured something strange, something that Lindberg has never seen in his eighteen years of experience doing deep-level sonar scans.

“Adding to the mystery at the bottom of the Gulf of Bothnia, Lindberg said he saw evidence of scars or marks disturbing the environment nearby, suggesting the object somehow moved across the ocean floor to where his team found it.” Writes Radford.

300 feet deep, and 60 feet across, the circular object stood out from the alien landscape. What is it? A sunken island? Crashed UFO?

Lindberg did state that he does not believe this to be a UFO, but a possible  “new Stonehenge.” Which makes more sense than a UFO.  I’m going on a limb here, but I say it’s neither. I say it’s the Millennium Falcon.

Read Ben Radford’s full post over at MSNBC.