The discovery of a beluga whale in Norwegian waters that may or may not be working for the Russian navy has captured worldwide attention.

Norwegian fisherman spotted the marine mammal on Monday wearing a GoPro camera harness with a label on the inside, written in English, “Equipment of St. Petersburg.”

The find alarmed Norwegian officials and led to speculation that the mammal may have been trained to spy for Russia. There is “great reason to believe” the whale was being used by the Russian navy, Martin Niuw from the Norwegian Institute of Marine Research, told the Norwegian broadcaster NRT. There is not yet conclusive evidence about where the whale is from, but that explanation for the whale’s origin is “entirely plausible,” says Gervase Phillips, a history lecturer who studies the military use of animals at Manchester Metropolitan University.

The Russian defense ministry has denied having a program that uses marine mammals, the Guardian reported.

That hasn’t stopped locals from joking that the whale has since “defected” to Norway; it is refusing to stray more than a few miles from the northern harbor where it was discovered.

If the whale is indeed a Russian spy, as speculated in headlines around the world, it would not be the first marine mammal drafted into military service. Here’s a history of whales, dolphins and other creatures that have been trained and deployed by militaries in Russia and around the world.