The longest tentacle of a giant squid found at South Bay in Kaikoura was more than five metres long.

This giant squid's body has washed on to the beach at South Bay in Kaikoura.

The massive deep sea creature caused quite a stir among walkers with its longest tentacle measuring more than 5 metres.

It has been moved to the Kaikoura Marine Centre and Aquarium for safe keeping.

The full scale of the squid at South Bay, Kaikoura. Photo: Kaikoura Marine Centre and Aquarium.

The centre posted on Facebook that the squid's body was about 2m long and its eye had a diameter of 19 centimetres.

"What a beast," the post read.

"Before the birds got to it - we got help to move it to the aquarium where it is safe inside a freezer with glass windows so you can see it. On display until we can do more with it."

Early walkers on South Bay were surprised to see the giant squid lying on the foreshore.

Bruce Bennett said he found the squid at 8.30am while walking his dog, something he does most mornings.

Bennett said the squid smelled slightly, and it wasn't on the beach on Tuesday so he assumed it washed up on Tuesday night.

A giant squid was found floating at sea off the Kaikoura coast in 2013.

Jack and Sharon Osikai found the 8m squid floating near Shark's Tooth when they were returning from a fishing trip.

It was dissected on TV3's Campbell Live show by Megan Bosch, a marine biologist at the Kaikoura Marine Centre and Aquarium.

She discovered that squid had been attacked by another, even bigger squid, which was apparent by the markings of a beak larger than its own on its tentacles and mantle (body).

A closeup of serrated suckers on the squid. Photo: Kaikoura Marine Centre and Aquarium

Bennett recalled the giant squid being found at sea but said he had never seen one washed ashore.

"I wish it had been a lump of [whale] ambergris [grey amber used in perfumes]," he said.

"I've found old fishing floats and bits and pieces of other stuff, never any ambergris."