He is suspected of having injured a gendarme in the arm during an altercation at the Col de Montgenèvre, a zone of passage for migrants, at the Italian border (Hautes-Alpes) last May.
The alleged aggressor of the military victim of an attack is the subject of a European arrest warrant.
According to BFMTV, which relays the information, this man is "a member of the ultra-left movement" and resides "in Italy".
On May 15, an altercation took place between ultra-left activists and the gendarmes, on the sidelines of a three-day pro-migrant rally, dubbed “Passamontagna” - “balaclava”.
The gathering was held in the town of Clavière, in the Turinese metropolis, on the Italian side.
No arrests in May
Among the gendarmes mobilized on the spot to secure the site on the French side of Montgenèvre, one of them had been injured in the forearm.
His injury was "not serious" - it was probably a fracture, indicate our colleagues from BFMTV - but still required support from the emergency services.
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The same day, the police present in Montgenèvre had also suffered jets of projectiles. They then used tear gas to "repel demonstrators who were trying to force the roadblock" which aimed to stop the influx of migrants, said the prefecture. No arrest had taken place at that time.