A French magistrate has opened a preliminary investigation into alleged embezzlement by three African leaders.
Presidents Omar Bongo of Gabon, Denis Sassou-Nguesso of Republic of Congo and Teodoro Obiang Nguema of Equatorial Guinea deny any wrongdoing.
The investigation follows lawsuits by the French branch of an anti-corruption group, Transparency International.
It has accused the three leaders of buying luxury homes and cars in France with money from African public funds.
William Bourdon, a lawyer representing the plaintiffs, told Reuters news agency: "This is an unprecedented decision because it's the first time a judicial inquiry has been opened concerning suspected embezzlement by sitting presidents."
Correspondents say the case could strain French relations with the three oil-producing countries.
Gabon and Republic of Congo are former French colonies, while Equatorial Guinea is a growing oil exporter.
The Paris prosecutors' office, which answers to the justice ministry, opposed the opening of the case on 20 April but investigating Magistrate Francoise Desset has allowed it to proceed.
A 2007 French police investigation found the leaders of the three countries and their relatives owned homes in upmarket areas of Paris and on the Riviera along with luxury cars, including Bugattis, Ferraris and Maseratis.
Mr Bongo came to power in Gabon in 1967 and is Africa's longest-serving ruler.
Mr Obiang has faced coup attempts since he seized power in oil-rich Equatorial Guinea in a coup three decades ago.
Mr Sassou-Nguesso took power in Republic of Congo for a second time in 1997 with help from Angolan troops.
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