The Kraken was a squid-like sea monster from Scandinavian folklore that was capable of attacking and sinking whole ships. Depictions of the creature often resemble a giant squid or octopus, but most likely the beast was merely a fictional creation. It never really existed ... or did it?

A recent video released by Greenpeace scientists on an expedition in the Bering Sea shows that sea monsters might be real after all. The hair-raising footage shows several jumbo squid viciously attacking the submarine research vessel. It almost looks like something out of a Hollywood horror movie. Video of the attack went viral after Greenpeace released it on Vine. You can watch it for yourself here:

The footage is clearly edited for dramatic appeal, but jumbo squid, also known as "red devils," have been known to attack before. Tales of fishermen falling overboard in squid-patrolled waters and never being heard from again are legendary. Divers who have encountered jumbo squid have had their masks torn off. They're a large, intelligent, aggressive species. But witnessing them attack a submarine raises the bar.

In the video, the squid can be seen squirting clouds of vision-obscuring ink while swimming frantically around the sub. At one point, a squid appears to transform into a fireball during the attack. The animals are equipped with color-producing chromatophores in their skin that are capable of generating brilliant light displays. They use this ability as a form of communication, to intimidate predators or confuse prey.

The Greenpeace submersible survived the encounter just fine, but this is definitely not an animal you want to come across as a diver. Capable of growing to more than 100 pounds and measuring over 6 feet in length, jumbo squid also possess more than 100 suckers on their tentacles that are each lined with sharp “teeth” that the animal uses when hunting prey. They can be found up and down the west coast of North and South America, from British Columbia to Chile.

Scientists don't believe jumbo squid are typically aggressive toward people, let alone submarines, unless provoked. It's possible they were frightened by the lights of the submersible, but the precise details of the encounter have yet to be released.

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