 A series of "Body Worlds" anatomical exhibitions has toured many countries worldwide, sometimes raising controversies about the sourcing and display of actual human corpses and body parts.Von Hagens maintains that all human specimens were obtained with full knowledge and consent of the donors before they died, but this has not been independently verified, and in 2004 Hagens returned seven corpses to China because they showed evidence of being executed prisoners.A competing exhibition, , openly sources its bodies from "unclaimed bodies" in China, which can include executed prisoners.