About 4,655 migrants were saved on Tuesday and 28 bodies recovered in more than 30 rescue missions off the Libyan coast, Italy's coast guard said on Wednesday.
More than 10,000 refugees have been picked up in just two days, as people smugglers take advantage of calm weather to push boats to sea. Over the same period, at least 50 people have died trying to make the dangerous crossing.
On Monday, about 6,055 migrants were rescued from about 40 boats, one of the highest numbers in a single day.
At least nine migrants had died and a pregnant woman and a child had been taken by helicopter to a hospital on the Italian island of Lampedusa, halfway between Sicily and the Libyan coast.
The latest surge in new arrivals means at least 142,000 migrants have reached Italy since the start of the year and around 3,100 have died.
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