Some 1,500 undocumented migrants landed on the Italian island of Lampedusa overnight, port authorities said today, following a report that dozens are missing from a boat that capsized.

The port said 21 boats carrying a total of 1,623 migrants including six women and six children have arrived on the island from Tunisian shores in the past 24 hours, adding that there had been "several rescue operations."

Italy's coast guard said five of the migrants who arrived had told the authorities they were rescued by another migrant boat from a vessel that capsized shortly after leaving Tunisia with 40 people on board.

In Tunisia, neither the police not the army were able to confirm the incident, but one member of the emergency services in the Tunisian port of Zarzis said a navy vessel had been sent to the suspected accident zone.

Thousands of Tunisians have arrived in Lampedusa in recent weeks, with many making the perilous Mediterranean crossing on rickety fishing boats.

French far-right leader Marine Le Pen visited Lampedusa yesterday and warned that Europe could no longer afford to host migrants from North Africa.

Italian officials say nearly 10,000 migrants have landed on Lampedusa since Tunisia's revolution in January -- more than the total number for 2010.