Crépin Mbengue Nyimbilo, a 30-year-old Cameroonian, his Ivorian partner Matyla Dosso, also 30, and their daughter Marie, 6, lived in difficult circumstances in Libya, where Crépin and Matyla first met after fleeing their native countries. Last month, the family of three set off on a clandestine crossing into neighbouring Tunisia, hoping for a better life. But arrested soon after, Tunisian police forced them to march back to Libya across a desert, with no food or water, like hundreds of other sub-Saharans amid Tunisia’s fierce crackdown on black migrants. The three became separated in the baking heat. Crépin miraculously survived but would later discover, on social media, that Matyla and Marie died of thirst and exhaustion in the desert. This is his distressing story, as told to Nejma Brahim.