The French internet publication Lies Breaker posted a video shot from above showing the two groups taunting each other, throwing bangers and other objects, and then joining together in conflict.
It was uncertain which side was which, or what was behind the conflict.
Damien Rieu, who describes himself on his Twitter account as a "whistleblower" and whose feed criticises Islamist groups, posted a mobile phone footage of the confrontation shot through a shop window.
Lyon : affrontement entre #giletsjaunes patriotes (à droite) et gilets jaunes d'extrême gauche (à gauche).
ActeXIII (Vidéo 2/2) ?? pic.twitter.com/VYnrufSqXO — Damien Rieu (@DamienRieu) February 9, 2019
As inevitable as night following day.— David Barrett (@SUBHCMole) February 9, 2019