Police last Friday searched the home and office of a financial adviser to France's richest woman as part of a probe into alleged illegal donations to President Nicolas Sarkozy's campaign, officials said.
The search of Patrice de Maistre's residence and firm came a day after police questioned the ex-accountant to Liliane Bettencourt, heiress to the L'Oreal cosmetics empire, about her allegations of cash gifts to Sarkozy.
Prosecutors have opened a preliminary investigation into claims by the accountant of a €150,000 donation from Bettencourt given to Eric Woerth, Sarkozy's campaign fundraiser in 2007 who is now labour minister.