They were working on a vehicle on fire in the Val de l'Aurence district in Limoges (Haute-Vienne).
According to franceinfo, police and firefighters were targeted by projectiles overnight from Monday to Tuesday.
These clashes lasted nearly five hours.
Around 11 p.m., firefighters and police intervened around this vehicle fire.
When they arrive, they are targeted by throwing stones, Molotov cocktails and mortars.
Barricades were installed, suggesting to a police source quoted by France Bleu that it was an ambush.
The perpetrators of the shootings are said to be about thirty young people wearing balaclavas who would have set fire to two other vehicles but preventing the firefighters from intervening.
The operation ended around 4 a.m.
There was no arrest.