Treasure dating back 1,000 years has been found by a tourist guide picking up litter in a crack in the wall of a cave which was the site of a Viking massacre.

The find, including unique silver jewellery, was made at Dunmore Cave, a natural limestone national monument in Co Kilkenny, at the end of the last tourist season.

As many as 1,000 people, mostly women and children seeking refuge in the cave, were slaughtered in the year 928, and many bones have been found over the years.

The haul was made up of silver and bronze objects and coins that can be traced back to before the start of the last millennium.

They included conical silver wire Viking age items not previously found anywhere in the world.

Experts believe they may have formed the personal wealth of an individual.

Officials from the Irish Government's Duchas heritage service today described the latest find as "very exciting and of major significance".

Treasure-hunters

The development was reported to the authorities late last year, but only confirmed on Friday.

The cave has been sealed off to keep out treasure-hunters with metal-detectors, and the artefacts have been transferred to Ireland's National Museum in Dublin for further examination, cleaning and restoration.

The haul is expected to go on show to the public later this year.

Duchas archaeologist Richard Buckley said: "These items were pricey at the time they were made - the Versace of the Viking period.

"They have not been seen anywhere else. It's an important part of the Viking jigsaw."

He added: "One of our guides was cleaning the cave. He was picking up discarded crisp packets at the time and found the jewels and coins in a crack in the wall."