Zimbabwe has flown up to 30 young elephants to a different country, believed to be China.The sale has been criticised by animal welfare groups, who say that the animals may be traumatised.But Zimbabwe's National Parks service argues that it needs to earn hard currency to support other wildlife during a devastating drought which has already killed 55 elephants.It has been a year since the animals were separated from their families.Tenashi Farawo, spokesman for Zimbabwe's National Parks, said proceeds from the sale of the elephants would be used to dig wells to save other wildlife in Hwangi National Park.He accused campaigners of using emotion to stir up undue public anger.But Lenin Chisaira, director of the Advocates4Earth environmental group, criticised the decision."We have been campaigning against the capture and sale of wild elephants and the way they are taken to places outside of their traditional areas. Usually they are taken to zoos and there they are broken down in a very cruel manner," he told the BBC.Widespread mining around the national park had affected water and grazing areas, Mr Chisaira said adding that it had the effect of "driving animals away" and requiring them to compete with other animals for water.In August, the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) approved a proposal stating that elephants from Africa should no longer be sold outside the continent - however, it is yet to be ratified.