sentences:  The basin has been divided into 21 blocks, and exploration rights have been awarded for many of them.Companies with concessions in the basin include Netherlands registered Pexco Exploration, Petronas (Malaysia), Lundin East Africa (Sweden), SouthWest Energy Ltd. (Hong Kong), and Afar Explorer (USA).The Ogaden War between Ethiopia and Somalia took place for the control of the region between 1977 and 1978, with a further clash in 1988.