By lunchtime on the first day of the conference, some of those attending were in tears-but they weren't crying over fraud losses.

A device designed to splatter dye on stolen money and incapacitate bank robbers with tear gas malfunctioned during a demonstration. The resulting emissions forced organizers to shut down the conference for the day.

The company that sells the dye packs, U.S. Currency Protection Corp. of Fountain Hills, Ariz., said the accident was caused by a combination of humidity and static electricity.

"It was a very freak thing," said Phillip H. Grimm, co-chief executive officer of U.S. Currency. "There is a one in a million chance of that occurring."

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