Scientists have captured footage of an elusive giant squid, estimated to have grown as long as eight metres, that roams the depths of the Pacific Ocean.
Japan's National Science Museum filmed the deep-sea creature in its natural habitat for the first time, working with the Japanese public broadcaster NHK and America's Discovery Channel.
The massive invertebrate is the stuff of legend, with sightings of a huge ocean-dwelling beast reported by sailors for centuries.
The creature is thought to be the genesis of the Nordic legend of Kraken, a sea monster believed to have attacked ships in waters off Scandinavia over the past millennium.
Modern-day scientists on their own Moby Dick-style search used a submersible to get them into the dark and cold depths of the northern Pacific Ocean, where at about 630 metres they managed to film a three-metre specimen.
After about 100 missions, during which they spent 400 hours in the cramped submarine, the three-man crew tracked the creature from a spot about 15 kilometres east of Chichi Island.
A museum researcher, Tsunemi Kubodera, says they followed the enormous mollusc to a depth of 900 metres as it swam into an ocean abyss.
NHK showed footage of the silver-coloured creature, which had huge black eyes, as it swam against the current, holding a bait squid in its arms.
For Mr Kubodera it was the culmination of a lengthy quest.
''It was shining and so beautiful,'' he says. ''I was so thrilled when I saw it first-hand, but I was confident we would because we rigorously researched the areas we might find it, based on past data.''
Mr Kubodera says the creature was missing its two longest arms. He estimates it would have been eight metres long if it had been whole.
He says it is the first video footage of a live giant squid in its natural habitat - the depths of the sea where there is little oxygen and the weight of the water above exerts enormous pressure.
Mr Kubodera, a squid specialist, also filmed what he says was the first live video footage of a giant squid in 2006, but only from his boat after it was hooked and brought to the surface.
''With this footage we hope to discover more about the life of the species,'' he said, adding that he planned to publish his findings soon.
Mr Kubodera says the two sightings of the squid were in the same area about 1000 kilometres south of Tokyo, suggesting it could be a major habitat for the species.
The giant squid - Architeuthis to scientists - is sometimes described as one of the great mysteries of the ocean, being part of a world so hostile to humans it has been little explored.
Researchers say Architeuthis eats other types of squid and grenadier, a species of fish that lives in the deep ocean. They say it can grow to be longer than 10 metres.