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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A milder night and staying frost free, with outbreaks of rain and misty low cloud for the hills and higher ground.
The Government is launching a consultation on whether to move Channel 4 out of London, Culture Secretary Karen Bradley has announced.
The PM wants a simultaneous negotiation of how much we owe the EU in unpaid budget liabilities and a future trade deal with the EU.