Von 1967 bis 1973, in der er dem Süden zugeordnet wurde, war er Kommandeur der Südvietnamesischen Befreiungsarmee und der stellvertretende COSVN. ###>*In 1966, he was assigned as Commander, Political Commissar cum Military Region V.From 1967 to 1973, he was assigned to the South, made Commander of the People's Liberation Armed Forces and Deputy Secretary of COSVN.