"It wasn't your typical fishing boat, it was a fairly large yacht, about 15 meters (50 feet) long," a spokesman for the local coast guard told AFP.

The migrants, all of whom were in fair condition, are being held at a processing centre near the landing point in Riace, in the impoverished southern region of Calabria, the tip of the Italian peninsula.

Crammed below decks while the yacht approached the coast without raising suspicions, they likely landed on the beach in small boats .

"For the most part now they don't come in fishing boats. They seem to have changed strategy," the spokesman said. "More and more it's motorboats or sailboats that don't attract as much attention. From outside they look like normal boats sailing for tourist purposes."

Police last week arrested two Turkish citizens aboard a 15-metre sailboat who allegedly had delivered illegal immigrants from Afghanistan and Iraq to Calabria.

About 50 of the migrants who landed Thursday were men, while the rest were women and children. Possibly 10 others had fled the scene and made their way inland, the coast guard said.

Two Ukrainians were also being held but it was unclear whether they were under suspicion for human trafficking.

Migrants questioned had given details of the yacht, which had set sail from Turkey, but the vessel itself was still being sought, the coast guard said.

"We are ready to welcome them," said the mayor of the town of Riace, population 1,700, which already hosts 130 migrants from Ethiopia, Somalia, Ghana, the Palestinian Authority and elsewhere.

"We have seen that migrants have become more of a solution to our problems rather than a problem," Domenico Lucano told the ANSA news agency, describing their presence as a "stimulus ... to overcoming the resignation that reigns in our region."

Until last year, most illegal migrants landed on tiny Italian islands south of Sicily, but since Italy and Libya reached an agreement that allows the Italian navy to repatriate migrants it intercepts at sea, the tide seems to have shifted east.

Italy's Interior Minister Roberto Maroni from the anti-immigrant Northern League party has said the agreement with Libya greatly contributed to an estimated 88 percent decrease in illegal immigrant landings over the past year.

But in the southeastern region of Apulia, arrivals of immigrant boats have almost trebled since the start of the year compared with the same period in 2009.

The coast guard said Thursday's landing was the biggest in recent years in the area.

The UN refugee agency and human rights groups dispute the accord's effectiveness and legality.

In its 2009 report on Italy, the Council of Europe's Committee for the Prevention of Torture warned that the return of migrants to Libya, where they face the risk of mistreatment, was a breach of Rome's obligations under the European Convention on Human Rights.