 Born in Debar in western Macedonia, Ostreni was a veteran who had served in the Yugoslav Army and until April 2001 was a deputy commander in the Kosovo Protection Corps.Ostreni was typical of ethnic Albanians, who saw no future for themselves in the post-independence Macedonian Army whose officer corps was dominated by Macedonians.Ostreni was not only a gifted tactician but also an author on military affairs who wrote a book on the partisan movement in Macedonia during the Second World War in which he examined the myth of a Macedonian/partisan democratic victory.