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Alleged child rapist nabbed hours after being added to FBI's 'Most Wanted' list

FBI via AP

The FBI had offered a $100,000 reward for information leading directly to the arrest of Walter Lee Williams, 65.

CANCUN, Mexico -- Mexican authorities arrested a former University of Southern California professor who faces sex crimes charges in the Philippines on Tuesday, just hours after he was added to the FBI's "Ten Most Wanted Fugitives" list.

The FBI named the 499th and 500th fugitives to the new edition of its 'Ten Most Wanted' list. NBC's Mike Kosnar reports on how the FBI uses media and public support to capture the world's most dangerous criminals.

Walter Lee Williams, 64, was arrested in the southern beach resort of Playa del Carmen. The FBI said he was an anthropology and gender studies professor at the University of Southern California until 2011.

Using academic research as a guise, Williams traveled in the Philippines and elsewhere in Southeast Asia to have sex with underage boys, according to the FBI. The bureau said it had identified 10 victims between ages 9 and 17.

The Quintana Roo state attorney general's office said police found Williams at a cafe on Tuesday night in Playa Del Carmen, a short drive from Cancun.

"He was sitting in a cafe," said state attorney general Armando Garcia. "It's not known what he was up to but he had a home in Cancun."

The FBI added Williams to its most-wanted list on Monday. The bureau was offering a $100,000 reward for information leading directly to his arrest.

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