Mexican police on Tuesday said they had discovered new developments in the thorny Florence Cassez case.

According to officials, a suspected kidnapper told them that Cassez, a French citizen, not only participated in abductions, but helped lead the 'Los Zodiacos" gang that carried them out.

Cassez was sentenced to 60 years in jail by a Mexican court for participating in at least three kidnappings. She was arrested in December 2005 with her ex-boyfriend and alleged gangster Israel Vallarta.

Cassez pleaded for extradition to France, and has maintained her innocence.

Mexican authorities arrested David Orozoco, a suspected member of Los Zodiacos, who claimed that Cassez was one of the masterminds of the abductions.

This comes as French foreign minister Bernard Kouchner said he wanted to press forward on her repatriation.

The French president and his Mexican counterpart Felipe Calderon met in Mexico in March and agreed to set up a "work group" to examine whether Cassez could be transferred to a French prison.

Two months on, no decision has been made.

The Cassez affair is a sensitive issue in Mexico, plagued by more that 8,000 abductions each year.

Ten days ago, Cassez once again begged Sarkozy to repatriate her, claiming she risks being infected by influenza A H1N1.