The missing Saas sheep – a Swiss breed whose numbers are in decline – were part of a larger flock of 350 brought down from the pastures to the village last Friday, reported newspaper Le Matin on Wednesday.

On discovering they were 103 sheep short, farmers sent search parties out to look for them, both on foot and by helicopter, but none were found.

The non-profit organization ProSpecieRara, which works to preserve rare species of plants and animals, said in a statement: “103 sheep cannot disappear like that. They must have been stolen by thieves.”

As the area sits on the Swiss-Italian border, police in both countries are involved in the hunt for the missing sheep.

Speaking to The Local on Thursday, Nicole Egloff of ProSpecieRara said it is unlikely the thieves stole the sheep to sell on.

"You can only sell them as Saas sheep, and only if they are registered in the studbook, which in turn is not possible without specifying they are stolen sheep. It's similar to when a famous painting is stolen – you cannot sell it without being exposed as a thief.

"So we are assuming that their meat was of interest. Sheep meat has a value of 200-300 francs, so 103 times that is a lucrative amount."

A species bred mainly in the Valais, Saas sheep are increasingly rare. In 40 years the population has declined by three-quarters to just 400 animals.

ProSpecieRara has been collaborating with local farmers to boost breeding of the sheep, which are distinguished by long, dropping ears and hook noses.