The number of migrants sailing from Africa to Italy resembles a "biblical exodus", the head of the Italian navy said yesterday.
Adml Giuseppe De Giorgi said his ships had rescued 18,546 migrants, including Syrians and sub-Saharan Africans, since October, following the deaths of 364 migrants when their boat caught fire.
The peak came this week when 4,000 were intercepted by the navy in 48 hours.
Angelino Alfano, Italy's interior minister, has claimed up to 600,000 migrants are preparing to sail from Africa as weather improves in the Mediterranean.
Adml De Giorgi said Italy was deploying large helicopter carriers, frigates, drones and helicopters carrying infra-red sensors to monitor the seas.