Norwegian officials say a beluga whale may have escaped a Russian military facility after local fishermen discovered the animal wearing a tight harness with Russian origins last week.

Key points: A beluga whale wearing a harness swam up to a Norwegian fishing boat last week

A beluga whale wearing a harness swam up to a Norwegian fishing boat last week One professor believed it was "most likely" that Russian Navy was involved

One professor believed it was "most likely" that Russian Navy was involved He said scholars in Russia and Norway had not reported any program or experiments using beluga whales

Joergen Ree Wiig of the Norwegian Directorate of Fisheries said "Equipment St. Petersburg" was written on the harness strap, which featured a mount for an action camera.

He said fishermen in Arctic waters last week reported the tame white cetacean with the tight harness to the directorate.

On Friday, fisherman Joar Hesten, aided by Mr Ree Wiig, jumped into the frigid water to remove the harness.

Mr Ree Wiig said "people in Norway's military have shown great interest" in the harness.

Experts speculated the whale came from an Arctic Russian naval facility. ( AP/Norwegian Direcorate of Fisheries Sea Surveillance Unit: Joergen Ree Wiig )

Audun Rikardsen, a professor at the Department of Arctic and Marine Biology at the Arctic University of Norway in Tromsoe, believed it was "most likely that Russian Navy in Murmansk" was involved.

Russia has major military facilities in and around Murmansk on the Kola Peninsula, in the far north-west of Russia.

Professor Rikardsen said he checked with scholars in Russia and Norway, and they said they had not reported any program or experiments using beluga whales.

"This is a tame animal that is used to getting food served so that is why it has made contact with the fishermen," he said.

"The question is now whether it can survive by finding food by itself.

"We have seen cases where other whales that have been in Russian captivity [are] doing fine."

Mr Hesten told Norwegian broadcaster NRK that the whale began to rub itself again his boat when he first spotted it.

Russian military trained dolphins during Cold War

Russia does not have a history of using whales for military purposes, but the Soviet Union had a fully-fledged training program for dolphins.

The Soviet Union used a base in Sevastopol on the Crimean peninsula during the Cold War to train the mammals for military purposes, such as searching for mines or other objects and planting explosives.

The facility in Crimea was closed following the collapse of the Soviet Union, though unnamed reports shortly after the Russian annexation of Crimea indicated that it had reopened.

The Russian Defence Ministry published a public tender in 2016 to purchase five dolphins for a training program.

The tender did not explain what tasks the dolphins were supposed to perform, but indicated they were supposed to have good teeth.

It was taken offline shortly after publication.

ABC/AP