Security protocols failed in preventing a major jewellery heist at the Louvre museum in Paris, leaving the country with a terrible image, France's justice minister has said.
Thieves wielding power tools broke into the world's most-visited museum in broad daylight on Sunday, stealing eight items described as of inestimable value, before escaping on scooters.
Security measures have been tightened around France's cultural institutions, advisers for the country's interior minister said.
There are fears that, unless the thieves are caught quickly, the priceless items, including a diamond and emerald necklace Emperor Napoleon gave to his wife, will be broken down and smuggled out of the country.
The Louvre announced it would remain closed on Monday while investigations continued.
French media reports that a preliminary assessment by the Court of Auditors (due to be published in November) found that a third of the rooms in the wing where the robbery took place have no surveillance cameras.
What is certain is that we have failed, since people were able to park a furniture hoist in the middle of Paris, get people up it in several minutes to grab priceless jewels, Justice Minister Gérald Darmanin told France Inter radio.
He added that he was certain police would eventually arrest the thieves.
But the head of an organisation specialising in the location and recovery of stolen artworks warned that if the thieves were not caught in the next 24-48 hours, the stolen jewellery will likely be long gone.
There is a race going on right now, Chris Marinello, the chief executive of Art Recovery International, told the BBC World's service.
Crowns and diadems - which were stolen in the heist - can easily be broken apart and sold in small parts.
The thieves are not going to keep them intact - they are going to break them up, melt down the valuable metal, recut the valuable stones and hide evidence of their crime, Mr Marinello said, adding that it would be difficult to sell these jewels intact.
The French police know that in the next 24 or 48 hours, if these thieves are not caught, those pieces are probably long gone, he said.
Interior Minister Laurent Nuñez said he was aware of a great vulnerability in museum security in France.
The decision to tighten security at the country's cultural institutions was made on Monday after a meeting with police and ministers, including Nuñez.
French President Emmanuel Macron described the robbery as an attack on a heritage that we cherish because it is our history.
And Nathalie Goulet, a member of the French Senate's finance committee, said it was a very painful episode for France.
We are all disappointed and angry, she told BBC Radio 4's Today programme, adding that it was difficult to understand how it happened so easily.
Goulet said that the gallery's alarm had recently been broken, and we have to wait for the investigation in order to know if the alarm was disactivated.
The cut-up jewels would be used in a money laundering system, she suggested.
I don't think we are facing amateurs. This is organised crime and they have absolutely no morals. They don't appreciate jewellery as a piece of history, only as a way to clean their dirty money.
The theft took place between 09:30 and 09:40 local time on Sunday morning, shortly after the museum opened to visitors.
Four masked thieves used a truck equipped with a mechanical lift to gain access to the Galerie d'Apollon (Gallery of Apollo) via a balcony close to the River Seine.
They then smashed glass display cases and stole the jewels, which collectively contained thousands of diamonds and precious gemstones. The entire robbery was over in around eight minutes.
