giant squid
Giant squid caught in Japan's northern sea. YouTube

A Japanese fisherman has said that he regretted mutilating a 160kg (360lb) giant squid that he and his crew caught while fishing off the island of Niigata.

The fishing crew had been looking to catch yellowtail from the icy seas off northern Japan when they hauled up the monster from almost a kilometre beneath the water's surface.

Footage of the catch made international headlines and the team made history by releasing the first live images ever taken of a creature of its kind, Reuters reported.

Giant squid are mysterious animals that are thought to have inspired the myth of the kraken, a sea monster that would attack and sink ships.

Shigenori Goto, 44, said: "We were about 30 minutes into our day when this large, reddish-brown thing came swimming up from the depths.

"I was surprised - there's no other word for it. We all started shouting 'giant squid, giant squid' all at once."

The squid died shortly after being hauled to the surface and during the attempts to land it, it lost its huge tentacles –something Goto now regrets.

"I wish we'd been able to make it more presentable," he said. "If I'd known it was going to be such a big deal, I'd have treated it with more respect."

Goto also said he had not thought of eating the squid, despite it being a popular dish throughout Japan: "If it had been smaller, we might have. But something that big really isn't all that edible."

Experts say the beast was probably around eight metres (26ft) in length, as the tentacles normally measure the same as the rest of the body.

Despite its huge size, for a giant squid the creature was not that big. The largest giant squid ever found measured 18 metres from its tail to the end of its tentacles.