Dec. 6 (UPI) -- Widespread strikes that has crippled services across France entered its second day Friday, bringing passenger rail service at a virtual standstill and grounding hundreds of flights.

The strikes, organized to oppose major pension reforms by President Emmanuel Macron, left commuters and tourists looking for alternative transportation on crowded French roadways.

Some union members who participated in the strikes Thursday, like school teachers, returned to work Friday but most transportation workers decided to continue the demonstration.

Some of the activists incorporated violence and vandalism into the demonstrations. Police responded to unruly crowds with tear gas and firefighters were called to douse flames set by the striking workers.

During rush hour Friday morning, officials estimated there were 215 miles of traffic in and around Paris. Many schools remained closed but some reopened.

About 90 percent of France's high-speed train traffic was canceled Friday, along with 70 percent of the local trains, according to French rail operator SNCF. Air France, easyJet and Ryanair all canceled flights after air traffic controllers and ground crews walked out. Those workers were joined by firefighters, hospital staff and teachers.

While Macron's pension reforms were the main catalyst behind the strikes, demonstrators have complained about other public service cuts and the president's efforts to reform France's social safety net model.

The strikes follow months of anti-government "yellow vest" protests, in which demonstrators initially revolted against rising fuel prices and taxes. The movement ultimately grew into a larger anti-government crusade that lasted for months.

Macron's pro-business administration is expected to negotiate with unions to try and prevent a long-term walkout that stretches beyond the holiday season. Macron has said although he's intent on the pension reforms -- which encourage workers to retire later -- he's keeping an open mind.