An official close to Interior Minister Laurent Nuñez said that by early Thursday, around 270,000 people had joined the union action in 180 rallies outside the capital.
About a third of France’s high schools were closed or unable to operate, some because of student blockades and others because teachers were on strike, The Associated Press reported.
Nuñez said the 70,000 police officers being deployed are backed by armored vehicles, drones and helicopters.
Authorities in the western region of Brittany also said "masked individuals" tried to block roads in Rennes, while some committed "serious acts of violence," including throwing steel balls at police.
France’s main unions warned that the country is on the brink of recession and that layoff plans are multiplying.
"Fuel, food products, rent, gas, electricity... everything’s going up except wages and pensions," they said in a joint statement, according to The Associated Press.
The U.S. Embassy had issued an urgent security alert for Americans in France ahead of the demonstrations, warning travelers to brace for severe disruptions, sudden curfews and the potential for violence.
The rallies come as the campaign to succeed Macron as president next May heats up, with political parties seeking to capitalize on the movement.
Macron is constitutionally barred from seeking a third consecutive term, while far-right candidate Marine Le Pen is the favorite to win, the AP reported.
Fox News Digital's Kelly McGreal and The Associated Press contributed to this report.