Image copyright UNICEF/Getty Image caption The missing couple were reportedly in financial trouble after their farm was badly hit in a cyclone

A New Zealand couple on holiday in Fiji have found a human head on a beach, the latest grisly discovery in an unsolved murder case in the Pacific nation.

In recent weeks a number of parcels containing body parts have washed up in Fiji, beginning with two pairs of human feet.

Police believe the body parts belong to a Russian couple missing from their farm on Fiji's main island since June.

Police and naval personnel are carrying out a full search of the area.

Police told local media that DNA tests confirmed the feet belonged to the couple, but have yet to receive results for the latest find. They have said they will not comment further on the case until the murder investigation is complete.

New Zealand couple Graeme and Jan Bickley had gone to Fiji for a week when Graeme spotted a bundle in shallow water during a walk on a beach.

"I scrambled in and grabbed hold, it was very, very heavy," Mr Bickley told Associated Press. "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'."

The missing Russian couple, named as Yuri Shipulin and Nataliya Gerasimova, were reported by the Fiji Sun to have been in financial difficulties after their farm on the island of Vita Levu was badly damaged by a cyclone in February.