Nuit Debout protestors clash with police in Paris

Protesters attacked shop windows and cash dispensers in the east of Paris on Thursday, a Paris police spokeswoman said.

"There are 300 people currently causing very important damage," the spokeswoman said, adding that a police operation was under way but no arrests had been made yet.

Several unauthorized marches have been taking place in Paris over the past two weeks on the sidelines of the occupation by left-wing and anarchist young people of the city's Place de la Republique, a vast square in the east of the French capital.

Earlier on Thursday, dozens were arrested after clashing with police at the margins of a rally protesting controversial labor reform plans.

The "Nuit Debout" or "Up all Night" movement began on March. 31 when a group of activists decided not to go home after a march against a proposed labor reform.

Crowds ranging from several hundred to a few thousand have gathered every evening since then for a spontaneous happening that is a mixture of street theater, party and ritual initiation for a new generation of activists.

Inspired by the Occupy Wall Street movement in the United States and Spain's 2011 Indignados street sit-ins, "Nuit Debout" unites the discontented in a mostly joyous hubbub of debate on everything from rewriting the French constitution to protesting against police violence and labor reforms.

Working groups on the square discuss utopian projects such as a universal income, a lifetime job guarantee or worker takeovers of companies, but also women's rights, the media, unemployment and climate change.

Veterans of the Spanish youth protests, which gave rise to the far-left Podemos (We Can!) party, came to Paris to offer informal advice on how to organize.

Hostility to government plans to make layoffs easier and cheaper, and encourage enterprise-level bargaining on working hours and wages, has prompted students and high school pupils to demonstrate alongside more traditional trade union marches.