HOUSTON – An American teacher who worked at various international schools is suspected of sexually molesting hundreds of students during his 40-year career, according to a report from United Press International.

Before taking his own life last month, William Vahey admitted to molesting many underage students, the news report said.  The Federal Bureau of Investigation office in Houston is currently looking into his past to determine the extent of his misdeeds.

Vahey worked at numerous schools in other nations that serve the children of Americans living there, including diplomats and military personnel.

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Administrators at one of those schools, the American Nicaraguan School in Managua, Nicaragua, recently obtained a thumb drive with images dating back to 2008 of teenage boys who appeared to be drugged. School officials said Vahey admitted to molesting some of the students, according to the report.

Officials believe Vahey may have assaulted as many as 90 of his students in Nicaragua on overnight field trips, the report aid. The victims may have been unaware of the abuse because they were unconscious.

Officials wonder how many other students he may have victimized at other schools over the years.

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

Florida teacher fired for sending dirty message to fifth-grader

A Florida teacher has been fired for allegedly sending sexually explicit messages to a fifth-grader using the popular social media application Kik Messenger, according to a report from WTSP.

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According to the news site, “Kik Messenger acts like any other typical messaging software like on a Smartphone, but the difference is that it does not need to be connected to a cell phone service provider.”

Robert Walrath, who taught at Compass Charter School in Bartow, apparently told her “what she could do with part of his anatomy,” according to a local police officer.

The state’s attorney’s office is still deciding whether to charge Walrath with any crimes.