More than 6,000 migrants have been rescued in the Mediterranean Sea in recent days while attempting to make the dangerous crossing from North Africa to Europe, an official said Tuesday, marking the resumption of a stubborn flow of people fleeing poverty and war.

The surging figures suggest that growing numbers of migrants, refugees and others — many from Africa and the Middle East — are trying to make the sea passage to Europe as the weather warms and smugglers increase operations.

The influx of people has become a major political issue in Europe, as anti-immigrant populists crusade against mainstream leaders and look to capture power in France and make gains in Germany in elections this year. European Union leaders have signed deals with Libya and some of the sub-Saharan countries that are sources of most of the current flow, but the root causes of the migration are as intractable as ever.

[Italy may be the next big migrant route]

The Mediterranean has become the main corridor for migrants trying to reach Europe aboard smugglers’ boats from Libya and elsewhere after authorities largely choked off sea routes between Turkey and Greece last year.

But the dramatic spike in Mediterranean rescues since late last week suggests even greater migrant traffic ahead, said Joel Millman, a spokesman for the Geneva-based International Organization for Migration, which monitors migrant flows and provides direct aid in refugee camps, detention centers and elsewhere. “This is typical of spring, getting very busy,” he said. “But it’s not typical to have the numbers be so high this early and the corresponding deaths that go with it.”

An estimated 500 migrants have drowned in the Mediterranean this year, and more than 20,000 have been intercepted at sea and brought to Italy and other European ports since January, Millman said. He said that if current trends hold, the traffic across the Mediterranean will be higher than it was last year but lower than in 2015, the peak year.

In the past few days, more than 6,000 migrants have been rescued, including about 3,300 taken to Italy and others found on overcrowded and foundering vessels off Libya, the base for many smuggling networks.

[Inside a smugglers’ haven in the Sahara]

The consistent flows are a sign that the deals European leaders have signed with African nations to try to restrict migration have not had a significant effect. Those deals link development assistance with the African countries’ efforts to keep their citizens from making the perilous journey to Europe, especially for economic opportunities. Refugees fleeing war are considered a separate category.

Most of the migrants taking the route from Libya to Italy come from sub-Saharan nations such as Nigeria, the Ivory Coast and Guinea. Syrians favored the safer, shorter route from Turkey to Greece, although that traffic has largely halted.

E.U. leaders last month agreed to give Libya $216 million to help bolster the fragile nation’s coast guard and navy so that they can stop smugglers’ boats inside their territorial waters. Europe also said it would help fund refugee camps in Libya and assist migrants who want to return to their home nations.

[Why the number of refugees drowning in the Mediterranean keeps rising]

But the high migration flows suggest that smuggling networks continue to operate at full capacity, with pent-up demand more than enough to mitigate any decrease due to the migration deals.

Millman said the traffic is likely to continue so long as legal routes to Europe remain limited, given the demographics of Europe and sub-Saharan Africa.

“Europe is desperate for cheap labor, and sub-Saharan Africans are desperate for these jobs,” he said. “Everybody has to decide what kind of system they want: a chaotic one that enriches criminals or an orderly one.”

Murphy reported from Washington.

Read more:

Meet the Libyan coast guard: Few ships, no lights, little hope of stopping migrants

Survivors recall sea tragedy as worries shift to Mediterranean migrant route

Another dead baby becomes the latest heartbreaking symbol of the Mediterranean refugee crisis

Today’s coverage from Post correspondents around the world

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