, the whale is known to local fishermen because it searches out boats and tries to free itself by rubbing the straps off against their hulls.
Fisherman Joar Hesten said: "We were going to put out yarn when we saw a whale whale swimming between the boats.
"It came over to us, and as it approached, we saw that it had some sort of harness on it.
"It always searches for boats and people, and then it comes all the way to the boat and tries to rub the straps off."
EXPERTS MYSTIFIED
Baffled experts have since said they believe it has escaped from a Russian Navy base in nearby Murmansk.
Martin Biuw, of the Institute of Marine Research in Norway, said: "If this whale comes from Russia – and there is great reason to believe it (does) – then it is not Russian scientists, but rather the navy that has done this."
And Audun Rikardsen, a professor at the Arctic University of Norway, told the broadcaster: "We know that in Russia they have had domestic whales in captivity and also that some of these have apparently been released. Then they often seek out boats."
He claimed he has contacted Russian researchers who denied having anything to do with whales in harnesses.
He added: "They tell me that most likely is the Russian navy in Murmansk. This is not a method scientists use."
VLADIMIR'S DOLPHIN BATTALION
Such a theory is not as unbelievable as it sounds - Vladimir Putin is known to have an army of military dolphins that can track mines and patrol waters.
And last year, a Ukrainian official claimed its trained military dolphins died "patriotically" after going on hunger strike when they were seized by Russians.
The highly-trained underwater assets refused to be flipped by their captors following Moscow's controversial annexation of the Crimea in 2014.
In the 1970s Ukraine's bottlenose dolphins were trained to carry out marine missions and were capable of planting bombs on ships and attacking divers with guns strapped to their heads.
The Ukrainian military had been developing the secretive unit based in Sevastapol on the Crimean Peninsula.
Borys Babin, the Ukrainian government's representative in Crimea, revealed they had died and claimed they did so while refusing to follow orders or eat food provided by the "Russian invaders".
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