Something anomalous is thought to be frequenting our oceans and we still have no idea exactly what it could be.
While unidentified aerial vehicles have been getting a lot of press in recent years, US Navy witnesses have also reported another, adjacent phenomenon - underwater aerial vehicles that seem capable of traveling at immense speeds and that can sometimes even transition into the air and vice-versa.

Speaking in an interview recently with former Republican congressman Matt Gaetz, Republican Tim Burchett - who has long maintained that the US government is withholding information on UFOs and alien visitors - described something that a US Navy admiral had allegedly told him.

"They tell me something's moving at hundreds of miles an hour underwater... as large as a football field, underwater," he said.

"This was a documented case and I have an admiral telling me this stuff."

Despite the implications of such a sighting, however, Burchett isn't too worried. "I'm not worried about [alien visitors] harming me," he said.

"I mean, with that capabilities, they would have barbecued us a long time ago."

Officially, the Pentagon - which has been investigating UFOs for years - does not acknowledge the existence of alien visitors. Last year, a formal report into the phenomenon concluded that there was no concrete evidence and that most UFOs sightings have conventional explanations.

Nonetheless, there are many - including some inside the US government - who remain adament that there is a lot more to the subject than officials are letting on.