"The release of the nerve agent Sarin in Tokyo's subway system on March 20, marks the first clearly non-state terrorist use of chemical weapons. The agent was highly diluted and fatalities were relatively few (10), though the number of injured was substantial (5,000+, with 600 hospitalized). This incident clearly indicates the potential political effectiveness of chemical weapons against an unprotected civilian population. Once a population has been sensitized by an incident like this, even the threat of CW can become significantly disruptive. Some have credited fear of another attack with contributing to the cautiousness of the Japanese police investigation."
CRS Report for Congress, 95-411
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