Two police officers were injured when protesters angry over labour reforms damaged stores and restaurants during an overnight march in Paris.
Thousands of people have been gathering for the past 11 nights in the French capital's Place de la Republique to express frustration at a Bill extending the working week and making layoffs easier.
The fledgling Occupy-style movement has expanded to include a range of grievances and visitors from other cities and countries.
Paris police said in a statement on Tuesday that a few hundred protesters broke off overnight and blocked neighbouring streets, overturning rubbish bins and smashing the windows of several businesses.
They said the protesters threw projectiles at officers who pushed them back.
Most of the protesters are peaceful. One group has been designated to debate a possible new constitution.