Airlines flying into France were ordered to slash schedules _ and to bring enough fuel for the trip out. Gas stations ran short or dry, while truckers jammed highway traffic Monday by driving at a snail's pace, a tactic known in French as "operation escargot."

Strikes over the government's plans to raise the retirement age to 62 from 60 disrupted daily life and a wide swath of industry _ from oil refining to travel to shipping _ as protesters fought a proposal they say tampers with the near-sacred French social contract.

Teens, who usually don't worry about old age, joined in the protests, with at least 261 high schools blocked or disrupted Monday. Some turned violent and 290 youths were arrested, the Interior Ministry said. Students set cars and tires on fire, toppled a telephone booth and hurled debris at police in the Paris suburb of Nanterre, as well as in Lyon and elsewhere. At least five police officers were injured.

Street demonstrations were planned in more than 200 cities across France on Tuesday _ the sixth nationwide day of protest marches since early September. Tuesday was also expected to bring more severe disruptions to air travel, trains, schools and beyond.

Many in France consider retiring at 60 a pillar of France's hard-won social contract _ and fear this is just the first step in eroding their often-envied quality of life. Critics say President Nicolas Sarkozy wants to adopt an "American-style capitalist" system and claim the government could find pension savings elsewhere, such as by raising contributions from employers.

The protests in France come as countries across Europe are cutting spending and raising taxes to bring down record deficits and debts from the worst recession in 70 years.

Sarkozy's conservative government points out that 62 is among the lowest retirement ages in Europe, the French are living much longer and the pension system is losing money.

"This reform is essential, France is committed to it, and France will carry it out," Sarkozy said Monday in the Normandy beach resort of Deauville.

With the measure expected to pass easily in a Senate vote this week, after being approved earlier by the lower house of parliament, victory could come at a high cost: The unpopular retirement reform is a key factor in Sarkozy's dismal approval ratings.

A poll published Monday in Le Parisien newspaper showed 71 percent of French people support or sympathize with the strikers. The telephone survey of 1,002 people by the CSA agency was carried out Friday and Saturday.

The strike by oil workers has been the most disruptive tactic yet _ and in response, the Interior Ministry opened a crisis coordination center Monday just to focus on the conflict.

Alexandre de Benoist, who heads the Union of Independent Oil Importers, estimated that about 1,000 of the 4,800 gas stations attached to large supermarkets had run out of at least one fuel product.

Prime Minister Francois Fillon has pledged to do whatever is necessary to prevent fuel shortages, and French Industry Minister Christian Estrosi said Monday there were enough backup stocks to last several weeks.

Still, fearful motorists flocked to gas stations in panic and found many empty, while aviation authorities told airlines flying in to France to make sure to bring enough fuel for the trip out.

Air France said four long-haul flights, including one from Seattle and another from Mumbai, made stops to fuel up Monday before reaching France to ensure they could leave again.

Bigger problems were coming Tuesday: The government ordered airlines to drastically cut back flights into France as labor unions plan new nationwide protests and strikes across the public sector.

France's civil aviation authority ordered airlines to cancel half of their flights Tuesday out of Paris' Orly airport, and 30 percent at other airports nationwide, including Paris' largest airport, Charles de Gaulle. Most disruptions were expected to hit short- and medium-haul flights.

Train traffic was also dramatically reduced from a nearly weeklong strike. France's SNCF railway operator said about half its high-speed TGV trains were canceled Monday, though traffic on the Eurostar between Paris and London was normal. Rail unions prolonged their walkouts through Tuesday.

Meanwhile, striking oil workers piled up tires and set them ablaze Monday in front of a refinery at Grandpuits, east of Paris, after authorities issued a legal order to reopen the facility. Workers said they would refuse, as curls of heavy black smoke wafted into the air.

Other employees and residents formed a "human chain" to prevent people from entering the plant.

"We hope to be heard by the government. We're aware that we must ... reform but we want a more balanced plan," Mohammed Touis of the CFDT union said.

Dozens of oil tankers remained stuck in the Mediterranean, anchored outside Marseille's two oil ports, where workers have been on strike for more than three weeks to protest a planned port reform as well as the retirement changes. Also in Marseille, garbage was piling up on the streets as trash collectors stayed off the job.

French truckers staged organized slowdowns Monday to snarl highway traffic. Cars and trucks drove at a snail's pace on the main highway between Paris and the northern city of Lille, with red union flags waving out the windows.

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Associated Press writers Jean-Marie Godard in Paris and Elaine Ganley in Grandpuits contributed to this report.