Japan's top court on Monday rejected an appeal against a death sentence for a member of the Aum Supreme Truth doomsday cult, in the final legal chapter on the deadly 1995 gas attack on the Tokyo subway. The Supreme Court turned down the appeal by Seiichi Endo, 51, who was sentenced to death for conspiring to produce the Nazi-invented sarin gas used in the attacks on the Tokyo subway in March 1995, a court official said. He also sprayed the gas in the central Japanese city of Matsumoto in June 1994. Endo was "health and welfare minister" in the Aum Supreme Truth sect's self-styled government and played a key role in its study of sarin, VX gas, anthrax and other germs and poisons. Presiding judge Seiji Kanetsuki said Endo "played a leading role in producing sarin gas, knowing what it would be used for," according to state broadcaster NHK. Monday's ruling is the final court procedure against the 189 Aum cultists indicted over the crimes. The Matsumoto gassing killed eight and the subway attack claimed the lives of 13 and injured thousands of others. Under Japanese law, Endo has 10 days to file an appeal against the top court's decision, but this is a purely technical legal procedure limited to the correction of clerical errors.