Bordeaux town hall has been set on fire as French protests continued over plans to raise the pension age.
More than a million people took to the streets across France on Thursday, with 119,000 in Paris, according to figures from the interior ministry.
Police fired tear gas at protesters in the capital and 80 people were arrested across the country.
The demonstrations were sparked by legislation raising the retirement age by two years to 64.
Fire engulfed the front door of the town hall in the southwest city of Bordeaux Thursday evening after a day of protests and clashes.
It was not clear who was responsible for the blaze, which was quickly put out by firefighters.
In Paris, generally peaceful demonstrations saw occasional police clashes with masked rioters who smashed shop windows, demolished street furniture and attacked a McDonald's restaurant.
One police officer who lost consciousness was dragged to safety by fellow officers.
