According to an aid organization, at least 44 migrants have drowned off the coast of Western Sahara.
As the organization Caminando Fronteras announced on Sunday, the migrants died when their boat capsized.
The Moroccan authorities arrested twelve survivors.
Only seven bodies were recovered.
Morocco controls most of Western Sahara.
Every year thousands of migrants try to reach the Canary Islands from Western Sahara.
According to the Spanish Ministry of the Interior, more than 40,000 migrants entered the country by sea last year.
In the same year, according to Caminando Fronteras, 4404 migrants died or are missing trying to reach Spain.
According to their own statements, the Moroccan authorities prevented more than 63,120 border crossings last year.
In the first three months of this year there were already more than 14,000.