According to the Chechens, the Algerians started it by beating up a 16 year old boy at a shisha bar. The Chechens then called in reinforcements from all over France.
Anyhow, my bet is on the Chechens.
It will be interesting to see if the French will be able to reign the Chechens in.
The Chechens have group solidarity + mafia mentality, so attempts to do so in e.g. Russia often flounder after some well-targeted threats to the relevant authority figures.