A Malian man has died after he and 50 other would-be migrants were dumped by the Moroccan authorities in the Sahara
The group, including citizens of Mali, Senegal, Gambia, Ivory Coast and Guinea had been trying to reach Europe in small boats when they were intercepted.
They were left in a desert border zone between Mauritania and Western Sahara without food or water, aid workers say.
Over 18,000 African migrants have arrived on the Canary Islands in boats this year, hoping for jobs in the EU.
"Neither the Moroccans nor the Mauritanians accept them on their territory," Ahmedou Ould Haye of the Mauritanian Red Crescent told Reuters news agency.
Spanish relief agency Medicos del Mundo said its members had brought them food, water and plastic sheets with which to build shelters.
Mauritania has reported finding the bodies of 16 migrants washed up on its beaches in recent days.
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