Gun them down.
....as Napoleon said...”...give them a wiff of the grape...”..
I suspect that the French police are capable of solving “problems with comunication” with time honored non-verbal methods.
Those cars were torched because the administration didn’t want to stop the burning. Le Flics could have but were not allowed to so do.
The next few days will be good ones for the bandage merchants in the Islamic ghettos of France.