A New Zealand couple said they found a cloth bundle containing a severed head while strolling along a popular Fiji beach in what has become the latest gruesome discovery in a murder case that has captivated the picturesque South Pacific island nation.

Similar tied bundles that washed ashore in late June at Natadola Beach contained two pairs of feet, according to local news reports.

Fiji police believe the victims in the unsolved murder case were Russian couple Yuri and Natalia Shipulin, who went missing from their farm on the main island of Viti Levu last month.

New Zealander Graeme Bickley told The Associated Press by phone Tuesday that he and his wife Jan had traveled to Fiji for a weeklong vacation in order to watch a rugby match and relax.

He said they were walking along the beach Monday morning when they spotted a bundle in water that was about 1 meter (3 feet) deep. Having heard about the murder case, he said, the couple joked that the bundle might contain more body parts.

But things soon turned serious.

"I scrambled in and grabbed hold, it was very, very heavy," Bickley said. "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."'

Bickley said the bundle was tied with a nylon line. He didn't want to disturb it further, he said, and so they left it until police officers arrived, who later confirmed it contained a head.

The Fiji Sun newspaper reported that the Russian couple was struggling to pay their bills after their farm was severely damaged by Cyclone Winston in February.

The Fiji Sun said the couple, believed to be in their late 40s, had moved to Fiji about five years ago and lived in a converted shipping container, growing pumpkins, watermelons and other fruits and vegetables which they sold to resorts and markets.

The paper said the couple's business partner had first reported them missing and that police had found the couple's car with the keys in the ignition at Natadola Beach.

The newspaper reported that divers plan to search the area for more evidence.

Fiji strengthened its diplomatic ties with Russia after some Western allies imposed sanctions following a 2006 military coup. The country has since returned to a democratic system of government.