The disappearance of hundreds of household cats has sparked calls for an official inquiry amid fears that they could have been killed, skinned and turned into blankets.

Concern has been fuelled by the existence of a legal Swiss trade in cat fur, which is reputed to be good for rheumatism. But cat blanket retailers have denounced allegations of widespread cat-napping across the border in France as absurd. They insist that they buy skins from wild felines killed in Switzerland and Britain.

Patricia Dolciani, head of the French Society for the Protection of Animals in Thonon-les-Bains, in the Alps, has called on the gendar-merie to launch an investigation.

She says her team has registered the disappearance of at least 550 cats in the region so far this year, more than double the number for the whole of 2006.

“What really raised our suspicions was when people started ringing to say they had lost more than one cat," said Dolciani. "One person near Megève, for instance, lost three in a day."

“It’s quite possible to lose a cat, of course. They can get run over. But three in the same day in the same place in the same family is more suspicious.”

The sense of panic gripping pet owners in the Alps was heightened when Marcelle Marchand, who has a refuge for wild cats, found one of her animals caught in a trap.

Albert Vercelotti was not so lucky.

Both his cats, Marx and Lisa, disappeared from his Alpine chalet, he said.

“We’re sad and unhappy," said Vercelotti. "We don’t know what happened to them.”

One theory put forward by the SPA is that the pets have fallen victim to traffickers feeding the fur trade on the other side of the border.

“You’re allowed to kill cats and sell their fur in Switzerland, unlike France," said Dolciani. “So perhaps that’s where the cats are ending up. We don’t know – they might be taken for laboratories who want to experiment on live animals or for other reasons, we don’t know."

“But it’s important that there’s an investigation so that the authorities can carry out a thorough investigation of the records of Swiss tanneries.”

Swiss media say that thousands of cat fur blankets are made every year, and almost are all sold to people suffering from rheumatism.

“I am totally mystified by these accusations," said Sylviane Ghielmini, who sells cat blankets at her shop in Yvonand, in the Vaud district. "The cat fur trade is small and not very lucrative and I really can’t see why traffickers would want to get involved. I sell ten blankets a year and all to people in pain with rheumatism. When these allegations broke I phoned my wholesalers and they said they’d never heard of anyone trafficking cats between France and Switzerland."

“One told me his supplier was in Switzerland and the other said it was in England," said Ghielmini.

Swiss tanneries say the trafficking claims have been propagated by animal rights activists in France as part of a campaign to ban the cat fur trade.

But Tomi Tomek, the founder of SOS Chats, a Swiss cat-protection association, said that she had contacted a tannery pretending to be a customer.

The owner said that he had about a hundred furs in stock and sent her three.

“He told me they were wild cats killed by hunters or peasants," she said. "But if that’s the case, where were the bullet holes?”