* In three days, navy says 5,200 rescued
* Merchant ships, Maltese vessel also involved in rescues
* Sicilian mayor says: "Europe can't turn its back"
By Steve Scherer
ROME, June 8 (Reuters) - Italy has rescued about 5,200 men, women and children and recovered three dead bodies from overcrowded boats in the Mediterranean Sea since early Thursday.
Calm seas have led to this latest wave of migrants who have left North African shores for Italy over just three days, a navy spokesman told Reuters, with merchant ships and a Maltese vessel also aiding in the rescue efforts.
The merchant tanker Norient Star recovered three bodies from one of the migrant boats, the spokesman said, adding that he had no details about the cause of the death or identity of the victims.
Three merchant ships, including the Norient Star, took aboard a total of 700 migrants, a navy statement said, and is taking them to ports in Sicily.
The surge in arrivals is straining the ability of the Italian naval mission - called Mare Nostrum or "Our Sea" - to patrol the waters between Africa and Italy on its own. It has prompted local officials in Sicily, where most of the migrants are taken, to call for more European support.
"Europe can't just turn its back on us," Lillo Firetto, mayor of the Sicilian port city of Porto Empedocle, said in a television interview on Sunday. "This isn't just Sicily's border, but it's Europe's border, too."
Italy has repeatedly asked for more European Union countries to join Mare Nostrum, which is Europe's biggest ever search-and-rescue mission, but so far only Slovenia has chipped in, offering one ship for two months late last year.
Mare Nostrum began last October after 366 migrants fleeing African countries drowned when their boat capsized a mile from Sicily. After the tragedy, the EU pledged 30 million euros ($40.85 million )in emergency funding, mainly targeted to fund immigration facilities on land.
The number of boat migrants who have reached Italy this year has already topped the total of more than 40,000 for the whole of 2013. The pace of arrivals is on track to exceed the record of 62,000 set in 2011 during the Arab Spring uprisings.
Two-thirds of the migrants, who come from dozens of countries and include Syrians fleeing civil war and Eritreans evading military conscription, leave Italy for other EU countries, the Interior Ministry said.
"The ones who arrived yesterday left immediately. We saw them walking down state-road 115," Firetto said in the televisions interview.
Given the thousands who have arrived in just the past few days, Firetto said he was very worried that the situation would get worse in coming weeks.
Prime Minister Matteo Renzi has urged the United Nations to intervene in Libya, where criminal gangs charge migrants more than $1,000 each for a spot on unsafe vessels, to try to limit the departures.
The recent flood of boat migrants has helped revive Italy's anti-immigrant Northern League party, which had lost much of its support over the last two years due to corruption scandals and leadership changes. ($1 = 0.7345 Euros) (Reporting by Steve Scherer. Editing by Jane Merriman)