At least 631 African migrants have died trying to reach Spain so far this year, nearly three times more than in all of 2017, and the situation has become "alarming," the U.N. migration agency said on Friday. More than 120 migrants, from North Africa and Sub-Saharan Africa, have arrived in Spain each day during November, following a record month in October with over 350 per day, the International Organization for Migration (IOM) said. "This is usually a time of slowing down on these routes; that is not happening in Spain," IOM spokesman Joel Millman told a news briefing, as reported by Reuters. Migrants are using smaller and less seaworthy boats, he said.

The sole survivor of another shipwreck, a teenage boy from Guinea now in hospital with severe hypothermia, told rescuers that he was travelling with nine others, including his brother, in an inflatable rowboat from Tangiers, Morocco.

So far this year, 104,506 migrants have arrived by sea in Europe and 2,075 have perished, according to the IOM's latest figures. Both figures are about two-thirds of last year's totals and around a quarter of the total from 2016. As the EU has yet to find common ground or a policy for saving the lives of migrants at sea, rights groups accused EU member states for the increase in the Mediterranean migrant death toll. The risk of dying in the central Mediterranean Sea has jumped to one in 18 for migrants this year as nongovernmental rescue ships face difficulties on this key route to Europe, the U.N. High Commissioner for Refugees (UNHCR) said in September.

In addition to migrants arriving by sea in mainland Spain, Millman said 36 migrants had died trying to reach the Canary Islands this year, compared to just one last year, Millman said. "So that is becoming also a dangerous channel for migrants seeking to access Europe through the Canary Islands," he said of the islands, which are a part of Spain located in the Atlantic Ocean off the Moroccan coast.

The journey by land through the Sahara and then across the Mediterranean remains the world's deadliest migration route and as polarizing as ever in European politics. Italy's Interior Minister Matteo Salvini, who is also the head of the far-right League party and a prominent member of the new Italian government, is leading a high-profile campaign to exclude humanitarian rescue ships from Italian ports. Besides Italy, governments in Austria and central Europe argue that the EU can only bring migration under control by closing its borders to new arrivals, while opposing efforts to redistribute asylum seekers within the bloc.

The arrival of hundreds of thousands of migrants into Europe has fueled the rise of far-right parties across the continent in recent years, although numbers have fallen over the past three years. Many thousands of people, mostly from Africa and the Middle East, have drowned at sea.

The number of migrants reaching the EU has in fact dropped sharply since the height of the crisis in 2015 when more than a million arrived from the Middle East and Africa, mostly by sea from Turkey to Greece and then overland across the Balkans. That route was largely shut down by a 2016 agreement between the EU and Turkey. The other main route, the frequently deadly crossing from North Africa to Italy, remains open, but numbers have declined substantially in the past year as Libyan armed factions have cut down on people smuggling. Still the issue remains sharply divisive across Europe.