2017 AP YEAR END PHOTOS - African refugees and migrants, mostly from Sudan and Senegal, wait for assistance aboard a rubber…
FILE - African refugees and migrants wait for assistance aboard a rubber boat, off the Libyan coast, Feb. 23, 2017.

At least 140 migrants drowned after a boat carrying more than 200 people sank off the coast of Senegal, the U.N. migration agency said Thursday.

The boat caught fire at sea and capsized Saturday, shortly after leaving the coastal Senegalese town of Mbour, according to the International Organization for Migration.

IOM said in a news release the boat was trying to reach Europe via Spain's Canary Islands but turned over near Saint-Louis along the northwest coast of Senegal.

FILE - Fishing boats are seen in Saint-Louis, Senegal, May 16, 2020.

About 59 of the migrants were rescued by Senegalese fishermen and the Spanish navy. Senegal's government and the IOM have arranged a mission to travel to Saint-Louis to assess the needs of survivors and provide psychosocial assistance.

The IOM described this incident as 2020's deadliest migrant boat wreck. Last year, 210 migrants died along the same route.

Growing numbers

The number of departures from West Africa to the Canary Islands has significantly increased in recent weeks.

In September alone, 14 boats carrying 663 migrants left Senegal for the Canaries. Of these departures, 26 percent were reported to have experienced an incident or shipwreck, according to the IOM.

IOM estimates there have been about 11,000 arrivals to the Canary Islands this year, about five times the number who had arrived by the same point in 2019. It said the 2020 figure, however, is still far below the peak seen in 2006 when more than 32,000 people arrived there.

The migration agency said in a statement it was deeply saddened by the tragedy and reiterated the need to "enhance legal channels to undermine the traffickers' business model and loss of life."

IOM Senegal Chief of Mission Bakary Doumbia said it will take "unity between governments, partners and the international community to dismantle trafficking and smuggling networks that take advantage of desperate youth."