An ethnic Bosniak, Reko was born in the hamlet of Gudelj of the village Jošanica in Foča in eastern Bosnia. During World War II his grandmother was saved by a Serb. He finished primary school in the village of Ustikolina, after which he moved to Sarajevo on higher studies, finishing middle technical school in 1982. He finished the Army military school in 1986 as an infantry. He served as an officer ("časnik") in Novo Mesto (in Slovenia), Gospić (Croatia), Pljevlja (Montenegro), Bitola (Macedonia), Zaječar (Serbia).