A £40,000 teddy which used to belong to Elvis Presley was among scores of toy bears destroyed when a dog meant to guard them went on the rampage.
Security guard Greg West does not know what made Barney do it
Dobermann Barney was looking after the rare Steiff bear, named Mabel, which had been loaned for an exhibition at Wookey Hole Caves near Wells, Somerset.
The dog ripped the head off the bear and attacked scores of other teddies.
Barney's owner could only suggest that the bear had a rogue scent on it - or that Barney had become jealous of it.
The bear, made in Germany in 1909, was bought at auction in Memphis, Tennessee, by Somerset aristocrat Sir Benjamin Slade.
Wookey Hole general manager Daniel Medley told the BBC: "About 100 bears were caught up in this frenzied attack, some were merely little chews, whereas some of them had some quite devastating injuries.
"Heads pulled off, arms, legs here and there, it was a total carnage really. I've never seen such a mess, there was stuffing, fluff and bear bits everywhere."
Barney also caused an estimated £20,000 damage to other bears in the collection.
Security guard Greg West, who was on duty at the time, is at a loss to explain what happened to make Barney go so "berserk".
Other teddies worth about £20,000 were damaged
Mr West, 36, of Totterdown, Bristol, said: "Barney has been a model guard dog for over six years. I still can't believe what happened.
"Either there was a rogue scent of some kind on Mabel which switched on Barney's deepest instincts, or it could have been jealousy - I was just stroking Mabel and saying what a nice little bear she was."
The attraction said Barney's future with them was "uncertain".