Scores of elephants have been killed for their ivory in Botswana in recent months as a southern African country once considered a sanctuary for wildlife has seen a surge in poaching. Poachers are thought to have killed at least 60 elephants in the past three months in the north of the country and in Chobe National Park, one of the world's top wildlife destinations. Gunmen are particularly targeting the few remaining "big tusker" elephants which have already been hunted to near-extinction.