During the morning rush hour on March 20, 1995, the Japanese cult Aum Shinrikyo placed packages on five subway trains converging on Tokyo's central station. When punctured, the packages spread vaporized Sarin through the subway cars and then into the stations as the trains pulled in.

The U.S. government has known since the early 1990s about Soviet-era smallpox weapons, and collected circumstantial evidence of programs elsewhere.

Smallpox, which spreads by respiration and kills roughly one in three of those infected, took hundreds of millions of lives during a recorded history dating to Pharaonic Egypt. The last case was in 1978, and the disease was declared eradicated on May 8, 1980.

Barton Gellman Quotes