(Reuters) – Gunmen in famine-hit South Sudan killed two people and wounded three when they attacked a humanitarian convoy in the center of the country, the International Organization for Migration (IOM) said in a statement on Thursday. South Sudan, the world’s youngest nation, has been mired in conflict since President Salva Kiir, an ethnic Dinka, fired his deputy Reik Machar, a Nuer, in 2013. The subsequent civil war split the nation along ethnic lines and has forced more than 3 million people to flee their homes.