Loïk Le Priol, the French far-right militant and main suspect in the killing of former Argentine rugby player Federico Martín Aramburú, was detained in Paris on Thursday following his arrival from Hungary, judicial sources have confirmed.
The 27-year-old former soldier and member of the Grupo Unión Defensa (GUD) white nationalist group will on Friday appear before an examining magistrate in the French capital where he will be formally indicted for murder.
After his appearance before the investigating magistrate, another hearing will be held before a so-called liberties and detention judge, which forms part of the French legal system and decrees the measures of judicial control or provisional detention.
Aramburú, 42, was shot dead in the early hours of March 19 after he and some friends were embroiled in a dispute with another group at a cafe in Paris's chic Saint-Germain neighbourhood.
Le Priol was arrested under a European arrest warrant on the night of March 22 at the Zahony border crossing between Hungary and Ukraine. Hungarian police said Le Priol told them "he was going to Ukraine to fight" against Russia's invasion of the country.
Three people have been arrested in connection with the murder of the 22-times capped Puma star, who scored a try as Argentina beat 2007 World Cup hosts France in the third-place play-off.
Romain Bouvier, 31, was charged with murder and two other crimes linked to possession of weapons. Also suspected of having shot Aramburú, he is being held at the Santé prison in Paris.
A 24-year-old woman, believed to be a former or current partner of Le Priol, was also charged and detained for "complicity of murder." Investigators believe the woman drove the vehicle from which both men allegedly fired the fatal shots..
Le Priol is previously known to the security services and holds convictions for violent offences at the age of 19 and 23.
In addition, he appeared in court back in June along with four other members of the GUD, including Bouvier, for violent acts against a former leader of this group.
In 2016, Le Priol launched a line of white nationalist clothing.
Aramburú also played club rugby in France for Biarritz, Perpignan and Dax from 2004 to 2010, winning the Top 14 twice with Biarritz and later sitting on the club's board of directors.
Since his retirement from sport, Aramburú had lived in Biarritz and worked for a tourism company.