People hold a banner reading "No to slavery" during a demonstration against discrimination in Nouakchott on April 29, 2015. Thousands of descendants of Moorish slaves in Mauritania, known as the "Haratin", protested in Nouakchott on the evening of April 29 against discrimination and to demand justice and equality for the Haratin. AFP PHOTO / STRINGER (Photo credit should read -/AFP/Getty Images)
