PARIS (Reuters) - Armed robbers stole gems worth 85 million euros ($108 million) from luxury jewelers in the heart of Paris, during a raid described by French media Friday as the most lucrative heist in France’s history.

The Harry Winston chain, long a favorite among the world’s rich and famous, once provided jewels to the Shah of Iran for his wedding and to Richard Burton for his wife Elizabeth Taylor.

A spokeswoman at the Paris prosecutors’ office said the Harry Winston store, located just off the Champs Elysees on an avenue of luxury outlets, had declared 85 million euros’ worth of losses to its insurers after Thursday’s hold-up.

“These are experienced bandits. They got through the main door without drawing attention to themselves. In less than 20 minutes they got up to the first floor, emptied the safes and the display cases and left through the door,” she said.

A police spokesman said the gang of four men, one or two of them disguised as women, threatened customers and pistol-whipped some of the staff. They appeared very well-prepared.

“Apparently they knew the names of several of the staff,” the spokesman said.

The raid came a year almost to the day after the same store was attacked by robbers who forced staff to empty its safes, taking at least $16 million worth of jewels.

Experts at the prosecutors’ office said the jewels and luxury watches stolen Thursday could not be sold in their present form as they would be too easily recognized. They said organized crime networks capable of finding buyers for the gems outside of France were likely to be involved in the heist.

The firm shows on its website a gem bought by the late shipping magnate Aristotle Onassis to present to former U.S. first lady Jacqueline Kennedy as an engagement ring.

It also has more recent pictures of movie actresses Gwyneth Paltrow, Hilary Swank and Scarlett Johansson wearing its jewels.

The French celebrity press reported earlier this year that President Nicolas Sarkozy gave a Harry Winston ring to model-turned-popstar Carla Bruni for their engagement, though the information has not been officially confirmed.