Police are investigating whether renovation work taking place at the rear of the Ritz Hotel in Paris contributed to a lack of security when it was raided by thieves.
Five men broke a window at the tradesman’s entrance to the famed hotel just after 6.30pm (5.30pm UK time) on Wednesday evening.
Three of the thieves went into the hotel armed with hatchets.
Inside, they smashed glass display cases and removed items worth “several million euros”, throwing some of their loot from the window to two accomplices outside.
Police have now recovered some of the jewels after they were scattered about during the arrest of the three suspects, while more jewels and watches were found in a bag dropped by one of the two robbers who got away.
One report suggests that one of the three arrested was dressed as a builder.
Witnesses at the hotel’s Hemmingway Bar saw the robbery unfold.
A witness told Sky News they heard “at least 10 rounds of gunfire”.
Nik said: “My parents and I were sitting at the Hemingway Bar at the Ritz for a drink and we were about to leave when we heard shouting from the bartenders to get down.
“One man wearing a ski mask ran right from the bar door to the front, right past my father.
“He had an axe in his hand. Immediately the bartender closed and locked the door and corralled everyone to the back kitchen area of the bar.
“We heard at least 10 rounds of gunfire so everyone dove behind the bar where we stayed there for about six minutes.”
Police union spokesman Jean-Michel Huguet would not confirm the use of guns by police or the thieves, but did confirm that the three men who entered the hotel were tasered and detained.
“Our colleagues are aware of the need for frequent routine patrols in these areas to watch and protect these luxury shops in the Ritz,” he said.
“They were close by and received a call that the villains had entered and were committing an armed robbery in the Ritz. So my colleagues intervened, neutralised and arrested the individuals who had smashed the presentation cases with all the jewels.”
The two accomplices escaped, one in a car, the other on a motorcycle.
A pedestrian was hit by the bike and lightly injured. The thief riding the bike dropped his loot and his weapons.
The award-winning French writer Frederic Beigbeder was also in the Hemingway Bar and said the place was very calm, according to French newspaper Le Figaro.
He is believed to have hidden in the basement.
It is understood that the police know the identity of the men, who are believed to be from the Paris area.
Place Vendome, where the Ritz is based, is also home to the Ministry of Justice.
Security in the area was increased in 2014 after several luxury jewellers were raided in violent robberies.
The Ritz has played host to scores of famous people since it opened in 1898.
Coco Chanel lived there for more than 30 years while Marcel Proust, F Scott Fitzgerald, Ernest Hemingway and King Edward VII were regulars.
The Luftwaffe set up their regional headquarters at the Ritz during the Second World War.
Mohammed al Fayed bought the hotel in 1979 and carried out major renovations to bring it back to its original popularity.
Princess Diana famously dined at the hotel with Dodi al Fayed before they both died in a car accident in the Pont de l’Alma underpass.