The 123 adults and children, most of whom say they are ethnic Kurds from Syria, were found on a beach on the Mediterranean island after being landed by traffickers -- who have not been caught.

They told French authorities they were trafficked by truck from Syria to Tunisia for up to 10,000 euros (14,000 dollars) each, and put on a cargo vessel which dropped them near southern Corsica on Friday.

The migrants were transferred to processing centres on the French mainland but judges in southern Marseille, Nimes and northwestern Rennes ordered 94 to be freed on Sunday, ruling that the state had no legal grounds to detain them.

In eastern Lyon a judge freed a further 10 on Monday while 19 others were expected to be released in southern Toulouse, refugees' rights groups said.

Migrants told the court in Lyon they fled Syria because, as Kurds, their rights were abused there and that they planned to file for asylum.

"In Syria I was not considered human," 35-year-old Jumsid Ali told the court. "I risked my life to come to France and I am sure that if I return to Syria I will risk death."

At least 61 of the 81 adults in the group have already filed for asylum, the immigration ministry said, and the others were expected to follow suit.

The interior ministry told AFP that as soon as the migrants filed for asylum applications, the procedure overruled any local procedures to deport them.

It was Corsica's biggest known mass-scale landing of migrants, who tend to try to enter Europe by sea via Italy, Malta, Greece or Spain's Canary Islands.

Several rights groups slammed the handling of the migrants and their transfer to detention centres.

"They are not 'illegals' living underground in France but refugees who after having arrived on French territory have the absolute right ... to seek asylum," said the League of Human Rights.

The UN High Commissioner for Refugees (UNHCR) on Saturday urged France to ensure each of the Kurds be allowed to seek asylum and to ensure a "complete and fair examination" of each case.

Immigration Minister Eric Besson meanwhile announced fresh plans for patrols to stop illegal migrants reaching the European Union and to target traffickers, after a meeting with immigration authorities.

President Nicolas Sarkozy's right-wing government has taken a hard line on immigration. In September it closed down a major camp for Afghan migrants in the channel port of Calais.