Convicted rogue trader Jerome Kerviel was arrested in southern France late on Sunday to serve a three-year jail sentence in a high-profile case he has depicted as one individual's struggle against high finance.
Kerviel, 37, has spent years fighting charges stemming from massive market bets that brought French bank Societe Generale close to collapse in 2008. He was convicted of breach of trust, forgery and fraudulent data manipulation.
For weeks, the former trader had been marching to Paris from Rome where he met the pope earlier this year, in protest "against the tyranny of financial markets". He had been followed by a crowd of reporters and live television crews.
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He had been required by French judges to report to a French police station by midnight to start serving his sentence, which was confirmed by France's highest appeals court in March.
On Sunday afternoon, Kerviel threatened to stay in Italy and appealed to France's president to intervene in his case. But he changed tack later on, crossed the border a little before midnight and was swiftly arrested by French police.
"The fight will go on. Whatever happens, Societe Generale and finance in general will continue to hear from me," Kerviel said a few hours before his arrest.
Kerviel has never denied masking his 50 billion-euro (40.7 billion ) positions, but he says his bosses knew what he was doing. The courts, however, have each time backed SocGen's insistence that the trader acted alone.
In March, France's highest appeal court upheld his three-year jail term. But it quashed 4.9 billion euros in civil damages that judges had ordered Kerviel to pay to compensate SocGen for its losses when the bank unwound the trader's positions in the midst of the financial crisis.
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Over the weekend, Kerviel appealed to French President Francois Hollande to give immunity to unnamed witnesses he said would be willing to testify in his favour. He claimed he was not guilty and that his criminal conviction was unfair.
The French president's office has only replied that if Kerviel asked for presidential grace, his request would be examined according to usual procedures. Kerviel rejected that offer, saying it would imply an admission of guilt on his part.
In an emailed statement on Saturday, a spokesman for Societe Generale criticized the media hype around Kerviel. He said Kerviel had been the subject of a meticulous investigation, judged three times and found guilty each time.