Natadola beach
File photo: Natadola beach, FijiKen K/ Flickr

A New Zealand couple were were left stunned after finding a severed human head on an idyllic Fiji beach in an unsolved murder case. The latest discovery comes after two pairs of feet washed up on shore last month.

Authorities conducted DNA tests and confirmed the remains belong to the pair, the Fiji Times reported.

Retired couple Yuriy Shipulin and Nataliya Gerasimova were described as "soul mates" by their friend, Alla Mallerich. They lived on a farm on the Nausori Highlands in Nadi.

The discovery was made as New Zealand couple Graeme and Jan Bickley took a stroll on one of the world's most beautiful stretches of sand on Natadola beach. As they walked along the beach, a bundle in the water caught the eye of Graeme Bickley.

"I went out in the tide and it was in knee depth water and grabbed it, it looked like a little bundle but it was very heavy of course," he told ONE News. "It was slightly bigger than the steering wheel and completely round and full of rocks," Bickley added.

"I scrambled in and grabbed hold, it was very, very heavy," said Bickley. "I dropped it on the sand and you could hear there were rocks in it. I looked at the shape of it, and thought: 'This isn't looking good'."

Mallerich befriended the couple after they arrived in the Pacific nation in 2011. She told the Fiji Times that Shipulin was "someone you could always count on" and added: "Yuri was a happy, easy going man who loved life, loved Fiji and he had plans to build his life in Fiji."

Police were joined by a team of divers from the Fiji Navy conducted a search in Natadola's waters for more body parts, police chief of intelligence and investigations, Luke Navela confirmed.

The Russian couple were reportedly in financial difficulties after Cyclone Winston caused severe damage on their farm earlier this year.