Wealthy businessman Félicien Kabuga outwitted prosecutors of the Rwandan genocide tribunal for more than two-and-a-half decades by using 28 aliases and powerful connections across two continents to evade capture.
The 84-year-old had been on the run for so long that the international tribunal set up to bring to justice those responsible for the 1994 genocide had ceased to work.
But he was eventually hunted down last weekend to a hideout in a suburb of the French capital - thanks to an investigation relaunched by Serge Brammertz, a UN war crimes prosecutor heading the body which handles outstanding war crimes cases for Rwanda and Yugoslavia.
"We knew already a year ago that he was very likely to be in the UK, France or in Belgium and we concluded only two months ago that he was in France," the chief prosecutor for the UN's International Residual Mechanism for Criminal Tribunals' (IRMCT) told the BBC.
"The French authorities located the apartment in which he was hiding, which led to the operation."
One of the major reasons he was able to be on the run for so long was "the complicity of his children", he said.