The armed robber at the Carlton Hotel in Cannes targeted a temporary jewellery exhibition it was hosting from a diamond house owned by Israeli billionaire Lev Leviev.
It remains unclear how many pieces were stolen.
The valuable jewels were due to be on public display until the end of August.
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Police have released CCTV in a bid to catch the thieves who raided a children's play centre, taking money from collection boxes and a till.
A hedgehog, a parrot, and a dozen dogs are among the pets needing new accommodation after the evacuation of the Chalcots estate.
Mixed fortunes across the UK tomorrow. Still breezy across the north.