A mystery Russian billionaire has outspent the richest of the rich, breaking a world record in splashing out $748 million on one of the most gorgeous villas on the French Riviera. The final sale price of the Villa Leopold, a Belle Époque mansion on the heights of Villefrance, has amazed real estate agents. On the otherhand, locals worry about the invasion of Russian money on the Côte d'Azur, and wonder if it is getting out of hand.

Russian oligarchs have been funnelling in money, and snapping up seaside properites at Cap Ferrat, Cap d'Antibes, Saint-Tropez and other playgrounds along the Riveria since the early 1990's. But none have come even close to what the unnamed Russian billionaire just paid for the Villa Leopold.

The mystery Russian just closed the deal with Lily Safra, widow of Edmond Safra, a Lebanese banker killed by an arsonist's fire in Switzerland in 2003. Safra is said to have held out for months as the buyer raised his bid for the villa.

Villa Leopold, located between Nice and Monaco, was acquired by King Leopold II of Belgium in 1902.