Clashes have broken out outside a major oil refinery in France after riot police moved in to clear strikers who blockaded the terminal for 10 days.
Two people were hurt outside the Grandpuits refinery east of Paris, one of 12 facilities affected by strikes.
President Nicolas Sarkozy ordered the authorities to lift the blockade earlier this week after thousands of petrol stations across France ran dry.
The Senate will vote later on the pension reform that sparked the action.
Ministers said the bill would clear its last major hurdle in a matter of hours, after the Senate was asked to halt debate on hundreds of opposition amendments and hold a single vote on all of them.
Changes to the retirement and pension age could become law next week, once they pass the committee stage and a final vote is held in both houses of parliament.
Police also acted to remove protesters from two fuel depots, in an attempt to restore supplies at the start of the school half-term.
Teargas was used to stop 200 demonstrators blocking access to a site near the southern city of Toulouse.
At a depot in Grand Quevilly in north-west France, police removed protesters for the second time in a week. The demonstrators had been cleared on Tuesday but reimposed their blockade two days later.
Hundreds of riot police were deployed in Lyon in an attempt to prevent a repeat of the sporadic violence that has broken out in the city in the past few days.
The unions have called two further days of protests on top of the rolling strikes in protest at the government's plans to increase the retirement age from 60 to 62 and the full state pension age from 65 to 67.
Around 100 police arrived at Grandpuits at 0300 (0100 GMT) with a local government official who said he had an order to reopen the plant.
The Total refinery at Grandpuits, the closest to Paris, is seen as critical for supplying fuel to the city and the main airports at Orly and Charles de Gaulle.
Union official Charles Foulard condemned the action as "a scandal" after police had acted in the middle of the night when the number of protesters was relatively small.
He said it was a disgrace that striking workers were being forced to help restart operations at Grandpuits under an emergency order.
"It's a grave moment for our democracy. Never, never have striking workers been requisitioned," he said.
A decree, known as a requisition, can compel strikers to return to work under threat of prosecution if the authorities believe there is a threat to public disorder.
A few hours later, dozens of strikers formed a human chain at the entrance to the refinery in an attempt to stop the requisitioned workers going in.
Scuffles broke out as police moved in to clear the entrance and minutes later workers were seen going into the refinery.
At least two people were hurt. One man was taken away by ambulance.
'Not much left'
The official who carried out the order, Seine and Marne prefect Jean Michel Drevet, said the blockade had been lifted before dawn so as not to provoke trouble.
He added that the decision had been taken by the government to alleviate the fuel crisis.
"There is not much left in the pumps," he said. "This will relieve some of that."
Production has been disrupted at all 12 of France's oil refineries as workers protest against the government's reforms.
Fuel depots and thousands of petrol stations across the country have been hit. People travelling to France from other countries are being warned they face disruption because of the strikes.
Oil industry officials met French Prime Minister Francois Fillon on Friday to discuss fuel supplies.
The head of the French Petrol Industries Association, Jean-Louis Schilansky, said afterwards that France could manage for several weeks by increasing imports and pooling reserves.
Energy Minister Jean-Louis Borloo said one in five petrol stations was still dry but he said the situation was gradually improving.
"Some days ago, 40% of the stations were dry. Then it went down to 30% and today it's between 20 and 21%," he said.
National protests against the raising of the retirement age began at the start of September, and earlier this week more than a million demonstrators took to the streets across France.
Youths have clashed with police in parts of Paris and Lyon as well as in other towns and cities.
Meanwhile, two police officers have been ordered to stand trial in connection with the deaths of two youths in a Paris suburb in October 2005.
Zyed Benna, 15, and Bouna Traore, 17, died after they ran into an electricity sub-station in the Paris suburb of Clichy-sous-Bois while they were being chased by police.
Their deaths sparked an outbreak of rioting and violence across the French suburbs which lasted for weeks.
The two police officers have been charged with failing to assist persons in danger.