A slide of migratory flows in the Mediterranean Sea from the Mare Nostrum operation is displayed in the control room of the Italian operation, which tracks and intercepts migrant ships en route to Europe.
Illegal immigrants watch from behind a fence as police patrol the perimeter of a detention center at Amygdaleza, on the northern fringes of Athens, on April 30, 2012.
A survivor of the shipwreck of migrants off the Italian island of Lampedusa looks out over the water Tuesday. The tragedy has bought fresh questions over the thousands of asylum-seekers who arrive in Europe by boat each year.
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