HOUSTON, April 22 (UPI) -- A teacher at international schools around the world may have molested hundreds of teenage boys after drugging them with sleeping pills, the FBI said Tuesday.

William James Vahey, 64, took his own life last month in Minnesota. The FBI in Houston is leading the investigation into his past.


The FBI said that Vahey was teaching at the American Nicaraguan School in Managua when administrators obtained a thumb drive that showed teenage boys who appeared to be drugged. The school said Vahey admitted molesting underage students and said he had been a victim of sexual abuse as a child. Vahey was jailed in California in 1969 on a charge of molesting children. But he was able to obtain positions at schools catering to the children of U.S. diplomats, the military, other expatriates and local families seeking U.S.-style schooling for their children, and was a popular and respected teacher and basketball coach.

Special Agent Patrick Fransen said the thumb drive held images going back to 2008, and suggested Vahey had molested at least 90 boys on overnight field trips. The boys may not have known of the abuse because they were unconscious. Investigators have learned that Vahey took students on field trips at other schools during his long career.

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“I’m concerned that he may have preyed on many other students prior to 2008,” Fransen said. “I’ve never seen another case where an individual may have molested this many children over such a long period of time.”

During his 40-year career, Vahey taught at schools in Britain, Venezuela, Indonesia, Saudi Arabia, Greece, Iran, Spain and Lebanon before his arrival in Managua.

The FBI is working with the State Department and foreign law enforcement agencies in the investigation.

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“At this time, investigators have no knowledge that Vahey shared or traded any of the pornographic material he made,” Fransen said. “But his suicide left a lot more questions unanswered than answered.”

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