Tokyo, Japan - A former cult leader who masterminded a poison gas attack on Tokyo subway trains in 1995 had his appeal against the death penalty rejected by Japan's Supreme Court on Friday.
Lawyers for Shoko Asahara, 51, had argued that the former leader of Aum Shinri Kyo, or Supreme Truth Sect, was mentally incompetent and called for the case be suspended.
Asahara, whose real name is Chizuo Matsumoto, was found responsible for gassings on Tokyo rush-hour trains that killed 12 and sickened thousands, and was sentenced to death by a Tokyo court in February 2004 for murder and attempted murder.
The attack injured about 5,500 people, some permanently, when members of the cult released sarin, a lethal nerve gas first developed but not used by the Nazis in World War Two.
Japan does announce dates of executions, which are by hanging, in advance of them being carried out.
The gassing, with its images of bodies lying across platforms and soldiers in gas masks sealing off Tokyo subway stations, stunned the Japanese public and shattered the country's self-image as a haven of public safety.
The nearly blind Asahara was also found guilty of other charges including a series of crimes that killed 15 people.
The son of a poor maker of "tatami" straw mats, Asahara graduated from a school for the blind before working as an acupuncturist and amassing wealth with sales of Chinese medicine in the early 1980s.
He later studied yoga and started a school to teach it, going on to set up the cult in 1987, mixing Buddhist and Hindu meditation with apocalyptic teachings.
Under Asahara, who had predicted that the United States would attack Japan and turn it into a nuclear wasteland, followers submitted to an ascetic communal life and performed rites such as swallowing water and then vomiting it up to "purify" them.
At its peak, the cult boasted at least 10,000 members in Japan and overseas, including some who had studied science at the nation's elite universities.
Raids on the cult's sprawling complexes at the foot of Mount Fuji after the subway attack uncovered stockpiles of high-tech equipment and dangerous chemicals.
Aum Shinri Kyo, which admitted involvement in the subway gassing, later changed its name to Aleph, the first letter of the Hebrew alphabet. Its leaders insist the cult is now benign, but Japanese authorities still keep its membership of more than 1,000 under surveillance.
In 2004, a Tokyo university revoked its acceptance of a 20-year-old woman after discovering she was Asahara's daughter, saying her presence could be disruptive.