Mysterious powder on bus investigated Tuesday, May 25, 2004 Bus isolated downtown near the Seabus station. CREDIT: Global BC Police investiged a mysterious substance on a Vancouver bus. CREDIT: Global BC A mysterious substance found on a Vancouver transit bus sparked a quarantine Tuesday in a downtown area that initially captured several reporters and TV camera operators. The problem started early in the afternoon near the Vancouver waterfront when a transit bus driver discovered a substance on the bus and immediately became sick. Two other people on the bus also became ill. All were treated on the scene by emergency crews. Police quarantined the area and sent in members of a hazard materials crew to try to determine the substance. Vancouver police spokeswoman Const. Sarah Bloor said reporters covering the incident had been released from the quarantine by early evening while others were being put through a decontamination process.