Thieves used stun gas to disable guards before stealing a white rhino horn from the Musée de la Chasse et de la Nature in Paris. According to local reports, the thieves broke into the museum at about 2pm, before making off with the horn of a white rhino captured in South Africa in the 1980s.

Rhino horn can be worth more than £50,000 per kilo – more than diamonds, gold and cocaine – and is particularly valued in Asia, where it is believed to cure cancer.

There were at least 20 incidents of rhino horn theft from museums, auction houses and private collections across the UK and Europe during the first six months of 2011, according to the Metropolitan Police.

Law enforcement agency Europol said the thefts were the work of a single gang.