Roissy-Charles De Gaulle airport outside Paris was hit Thursday by wildcat strikes by workers. Near Toulouse in the southwest, burning piles of debris blocked traffic on a highway and sent plumes of smoke into the sky.
"There is a lot of anger, an explosive situation," the leader of the hardline CGT union, Philippe Martinez, said at the start of a rally in Paris. Union leaders called for calm but were angry with what they called Macron's provocative comments.
Police fired tear gas at protesters in the western city of Nantes. In Rennes, they used water cannon, BFM TV footage showed. Also in the west in Lorient, Ouest-France newspaper said projectiles triggered a brief fire in the yard of a police station.
"I'm on strike to protest against the pensions reform, but also against what is happening in the government," 27-year-old Air France programming officer Lucile Bidet said at a rally in Nantes.
"They're not listening to the people anymore."
Electricity output was also cut on Thursday as unions raised pressure on the government to withdraw the law. Flight services will continue to be reduced at the weekend, the civil aviation authority said.
Protests also targeted oil depots and blocked an LNG terminal in the northern city of Dunkirk.
Protests against the new law, which also accelerates a planned increase in the number of years one must work to draw a full pension, have drawn huge crowds in rallies organized by unions since January.
Opinion polls have long shown that a majority of voters were opposed to delaying retirement age by two years to 64.
Voters were further angered by the government's decision last week to push the pension changes through parliament without a vote and by Macron's comments on Wednesday.
Macron broke weeks of silence on the new policy to say he would stand firm and the law would come into force by the end of the year. He compared the protests to the Jan. 6, 2021, storming of the U.S. Capitol.