The international wildlife trade group, Traffic said that due to huge demand in Asia, more elephant tusks were　seized in 2011 than in any year since 1989, when the ivory trade was banned. 　　Year 2011 is described by the group as a "horrible year" for elephants, with 23 tonnes of ivory seized, representing at least 2,500 elephants being killed. 　　Trade in ivory was banned in 1989 to save elephants from extinction, however, illegal poaching continued because of huge ivory demand in Asian countries, such as Chain and Thailand, where some believe ivory has medicinal properties. 　　They said that the increasing ivory demand reflects both a rising demand in Asia and the increasing sophistication of the criminal gangs behind the trafficking. 　　Environmentalists say that some southern African countries, whose elephants populations are booming, allow people to sell ivory. However, the decision has fuelled the illegal trade. 　　In response, those countries, including South Africa, Botswana, Namibia and Zimbabwe deny the allegation and argue they should be rewarded for monitoring their elephant populations.