The majority of the world's supply of raw opium used in the manufacturing of heroin originates in Southeast and Southwest Asia. Kuhn Sa, the leader of the Shau United Army headquartered in the forests of Burma, is the most prominent Asian figure in the opium and heroin trade. Oriental gangs compete to control the drug market in many areas of the world, including some parts of the United States. Chinese Triads and their U.S. counterpart Tongs have a long history of criminal involvement and fit the classic structure of an organized crime group. They have a hierarchy and chain of command, require sponsorship of new members by existing ones, and have an initiation ceremony for recruits. Triads and Tongs have infiltrated legitimate business in many U.S. cities to launder capital from drug sales. The Japanese Yakuza, probably the largest organized crime group in the world, is active in drug trafficking, focusing on the acquisition of amphetamines (and firearms) from the United States and smuggling them to Japan. The Yakuza has also infiltrated many legitimate businesses in the United States for the purpose of laundering drug money.