Vietnam's apparent reluctance to share DNA samples of smuggled horns with South Africa - the country with the largest remaining populations of rhinos in the world, albeit decimated by a relentless wave of poaching over recent decades - has been criticised by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) Listen to this article 11 min Listen to this article 11 min Vietnam has come under fire for its 'passive approach' to sharing crucial evidence that could help South African forensic experts trace the exact origin of horns smuggled illegally to the Southeast Asian nation recognised as a primary driver of the rhino poaching crisis.