Authorities said the hold-up took place in broad daylight at the Carlton Hotel on the promenade in Cannes, famous for its annual film festival that attracts a glittering array of celebrities.
Hotel management declined to comment.
During the film festival in May, thieves stole jewellery worth $1.4-million that was due to be loaned to movie stars from a local hotel in a pre-dawn heist.
That robbery took place in the hotel room of an American woman employee of Swiss jeweller Chopard while she was out for the evening, police said.
A strongbox containing jewels was ripped out of the wardrobe and carried off, they said. – Sapa-AFP