Aum Shinrikyo and the Japanese law on bioterrorism.

Before the sarin incidents in Tokyo and Matsumoto, the Aum Shinrikyo (now Aleph) had tried to conduct bioterrorism with botulinum toxin and Bacillus anthracis. Followers of the Aum could not overcome technical difficulties inherent in developing biological weapons, and the perpetrators had not been prosecuted for their failed attempts of bioterrorism. But the Aum's biological attack revealed several shortcomings in the Japanese law that regulated biological weapons. Since the missile experiment of North Korea conducted in 1998, the Japanese government has come to consider the threat posed by biological weapons more seriously. In 2001, after the 11 September 2001 terrorist attacks and the series of anthrax letter scares in the United States of America, the Japanese government established its Five Basic Principles for Chemical and Biological Weapons Terrorism and several measures were taken at the central and local levels. Activities of the Aum have been monitored by the Public Security Investigation Agency and the National Police Agency under the Anti-Aum Law since 2000.