Protesters in Paris smashed store windows and damaged cars after French President Francois Hollande said he would not abandon a labour bill that has prompted weeks of sometimes violent demonstrations.
Paris police say groups of troublemakers damaged a supermarket, a jobs centre, bus stops and electric cars used in a municipal car-sharing service, among other businesses, in a late-night march on Thursday.
The violence came shortly after Hollande was questioned on national television about the bill, which is aimed at loosening labour rules to encourage companies to hire.
Hollande's left-wing base considers it a betrayal of France's hard-fought worker protections.
The government has amended it in the face of resistance, but Hollande insisted: "It won't be withdrawn."
Most of the protests, led by unions and students, have been peaceful.
