In a statement, police said some 300 officers had been involved in the vast sweep of arrests, which focused on hundreds of military-grade arms, pieces of ammunition and weapons parts trafficked from the Balkans and Slovakia since 2009.
The arrests were carried out across France and in various French overseas territories. Arrests were ongoing, police said, and 38 people had been placed under formal detention.
The investigation was launched after several military handguns and rifles were seized during an arrest in the Haute-Marne region in February 2012.
The investigation initially pointed to a Slovak arms trafficking ring and expanded to include another ring based in the Balkans.
An influx of military-style weapons, in particular Kalashnikov assault rifles, has been blamed for a wave of gang-related shootings in the southern city of Marseille in recent years.
More to follow.