LOUISVILLE, Ky. (WDRB) -- The FBI is seeking help to identify victims of a suspected serial child predator who taught in private American international schools for four decades.

The suspect, 64-year-old William James Vahey, killed himself last month after his employer found a thumb drive belonging to Vahey that contained pornographic images of boys who were likely drugged.

At the time, Vahey
was teaching world history and geography at the American Nicaraguan School in Managua

FBI agents in Houston filed for a warrant March 19 to search the thumb drive after an a school employee gave the drive to the U.S. Embassy.

Special Agent Patrick Fransen says the thumb drive contains pornographic images of at least 90 boys, aged 12-14, who agents suspect were Vahey's students starting in 2008.

But Fransen says Vahey taught at American international schools since the 1970s, raising concern that there may be even more victims.

The FBI says Vahey told a Nicaragua school administrator that he drugged his victims and preyed on boys his entire life.

Among his many stops during his four-decade teaching career, Vahey taught at American schools in
Nicaragua, the United Kingdom, Venezuela, Indonesia, Saudi Arabia, Greece, Iran, Spain and Lebanon.
His victims could include foreign nationals and American children of diplomats and military personnel.

According to investigators, Vahey used sleeping pills on his victims, who may not remember the sexual abuse.

is available for anyone who thinks they might be a victim.

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