Evidence of ancient introgression from an unknown, extinct human population in Africa. Application of a novel ABC-DL model revealed that the best fit to the data is a model assuming introgression (~4-6%) from an unknown, archaic human lineage (the so-called "ghost population") to the ancestors of the Khoisan, Mbuti and Mandenka. This lineage separated from the ancestors of Homo sapiens about 528,000 years ago - before the separation of Neanderthals and Denisovans. The study's findings challenge simplistic models of Homo sapiens evolution in Africa, suggesting a complex demographic history involving extinct human populations that left no traces in the fossil record, but are evident in the genomes of modern Africans. The study also underscores the need for broader representation of African populations in genetic studies.