Through the development agency FIAP, the Spanish government is launching two migrant detention facilities that even include cribs, allowing authorities to hold minors. These centers, located in the Mauritanian cities of Nouakchott and Nouadhibou, are part of Spain and the European Union’s border-externalization strategy, which consists of outsourcing the repression of irregular migration flows to African regimes. In recent months, Mauritania has become the departure point for thousands of migrant boats headed to Spain’s Canary Islands. Since then, Spanish and European authorities have increased their transfers of funds and police equipment to the country. This investigation also shows how the Mauritanian authorities, with support from Spanish officers deployed in the country, arbitrarily detain Black people, imprison them in inhumane conditions, and ultimately abandon them in desert areas such as Gogui, on the border with Mali—a zone with a strong presence of JNIM, Al-Qaeda’s Sahel affiliate.