A gallery attendant on duty at the Louvre when thieves broke in and stole eight of France's crown jewels has said no-one could have been prepared for what unfolded as visitors began to arrive on Sunday morning. All of a sudden we heard a huge noise, she told radio station France Inter, in the first account given by an attendant at the scene. The unnamed attendant and two colleagues initially thought the noise to be an angry visitor, but it was not a normal sound: It was a dull, slightly metallic noise. It was, in fact, the moment thieves had used an angle grinder to burst through a reinforced window into the Gallery of Apollo, where the Louvre's collection of historic jewelry is kept. Within eight minutes, the gang seized treasures, including a necklace that belonged to Napoleon's wife Empress Marie-Louise and a diadem of Napoleon III's wife Empress Eugenie, worth an estimated total of €88 million (£77 million). The thieves used a mechanical ladder on the back of a lorry to lift them to a first-floor balcony to gain entry to the gallery. Two tourists ran towards them in panic, she said. I saw one of the criminals turn around with something that looked to me like a chainsaw, then I yelled at my colleagues to get out, she recalled. She shouted a second time that it was a robbery and that they should run. One of her colleagues raised the alarm over a walkie-talkie and then we finished evacuating the visitors without quite realizing really what was going on. They shut all the doors as they left to protect the neighboring galleries. On reflection, the attendant said for us it was unbelievable the display cases could have been broken... never for a moment did we think there was such a risk... nobody can be prepared for that.