The armed raider strolled into an exhibition of "exceptional jewellery" around midday, The Independent reported citing initial reports.

The thief seems to have acted alone. He stuffed a small suitcase with jewels, and made his getaway. No violence was used and it was immediately unclear how many pieces had been stolen from the exhibition, organised by the Moscow-based Leviev diamond house, owned by the Israeli billionaire Lev Leviev.