BASTIA, Corsica — French police commandos swooped onto the deck of a ferry seized by striking sailors in the Mediterranean Sea, recapturing the vessel yesterday and steering it back toward mainland France.

The commandos slid down ropes from five helicopters onto the Pascal-Paoli in the dramatic morning operation off the coast of Corsica island. The ferry can carry more than 500 passengers but none were aboard at the time.

A few minutes later, the ferry changed course back toward mainland France under helicopter escort. TV images showed sailors handcuffed and kneeling on the deck.

French Prime Minister Dominique de Villepin ordered the operation, involving about 50 commandos who had warned the crew of the pending assault, according to his office and a military spokesman.

Union leaders angry over government plans to privatize troubled state-run ferry operator SNCM commandeered the vessel on Tuesday and steered it toward Corsica.

Butler Capital Partners, the private investment firm picked by the government to take over SNCM, said 350-400 jobs might be lost in the privatization.

Shortly before the assault, union leader Alain Moscini told France-Info radio: "We are not warriors, as we are only fathers of families. ... We will be arrested with dignity.

"They succeeded in their big military action. They defeated a handful of unarmed Corsican sailors," he said afterward.

French prosecutors filed a complaint for hijacking against the strikers, which is punishable by 20 years in prison, media reports said.

The raid came as striking workers shut down the port of Marseille for a second straight day, and protests continued in Bastia, in northern Corsica.

About 200 protesters poured into downtown Bastia, clogging road traffic and blocking the port. About 30 riot police were forced to retreat to a secured road where government offices are located.

The conflict at sea and on land was a new challenge to the government of de Villepin, a presidential hopeful who is navigating in stormy political waters almost four months after taking office.

De Villepin's plan to revive the popularity of a beleaguered center-right government centers on reducing unemployment and spurring economic growth. He has cultivated an image as a defender of the working man and of French interest against foreign corporations.

The owner of Butler Capital Partners is a French-American businessman described by French news reports as a friend of de Villepin and other powerful officials.

Moreover, the clash has escalated at a time when France's aggressive unions are gearing up for the customary fall season of disruptive strikes and marches.