Mysterious poison fumes overwhelmed rush-hour subway commuters today, killing at least five people, sending more than 200 to hospitals and paralyzing the city's sprawling transportation system.
At least 10 people were unconscious and listed in critical condition.
The Tokyo Metropolitan Fire Department said the first report came from Tsukiji station in central Tokyo shortly after 8 a.m. Passengers reported that a man in his 40s placed a lunch box wrapped in newspaper on an overhead rack inside a subway car and then got off. Shortly after, passengers began coughing and complaining of headaches, blurred vision and nausea.
Kyodo News Service reported that a bottle wrapped in newspaper was also found inside a subway car, raising suspicions that the perpetrator had left gas bombs in several places. At least 15 stations on two major subway lines reported cases of passengers collapsing.
Police first identified the toxic material as acetronitrile, a colorless liquid used in the synthesis of organic materials. The NHK TV station also reported that the material might have included sarin, a highly toxic nerve gas that killed seven people in Nagano prefecture last year, and police later said sarin could have been mixed with acetronitrile.
A similar poisoning occurred earlier this month on the Keihin Kyuko line headed from Yokohama to Tokyo. In that incident, a colorless gas filled the train shortly after midnight and overwhelmed 19 people who complained of headaches, blurred vision and nausea. Eleven people were sent to hospitals.
Police said they were still investigating whether today's incident was related to the Keihin and Nagano poisonings.
Japanese news broadcasts showed morning commuters collapsed on sidewalks, their faces contorted in pain as they loosened their neckties and mopped sweat from their brows. Rescue workers administered CPR to prostrate passengers, while others scurried to transport the injured by ambulance to nearby hospitals.
"I couldn't stop coughing," one female passenger told Japanese television. "I had no idea what was going on."