(LOS ANGELES) -- Walter Lee Williams, the former professor who was nabbed in Mexico after spending one day on the FBI's Most Wanted list, is expected to make his first court appearance in Los Angeles on Thursday, authorities said.
Williams, 64, who is accused of engaging in sex acts via webcam and in person with underage boys in the Philippines, was arrested in the Mexican resort town of Playa del Carmen on Tuesday after a local resident saw his picture in the media and alerted authorities, said Bill Lewis, assistant director in charge of the FBI's Los Angeles field office.
The person who tipped off authorities is believed to be a Mexican citizen, Lewis said, and will be eligible for the $100,000 reward the FBI was offering for information leading to Williams' arrest.
"Having him as a top 10 fugitive is what really led to his capture," Lewis said.
Williams, who used to be a professor at the University of Southern California, where he specialized in anthropology, history and gender studies, is believed to have more victims, said Michel Moore, assistant chief of the Los Angeles Police Department.
"We believe there are other victims who have suffered by this man's actions and we need to talk with them," he said.
Williams is charged with one count of producing child pornography, one count of traveling for the purpose of engaging in illicit sexual conduct with a minor, and two counts of engaging in illicit sexual conduct in foreign places, according to a statement from the Department of Justice.
According to officials, Williams met the underage boys online and engaged in sex acts with each of them over a webcam. In January 2011, he traveled to the country where he had allegedly had sex with the boys and even "produced sexually explicit photos" of one of them, according to the DOJ.
On Monday, Williams became the 500th person to be placed on the FBI's Most Wanted list.
"I analyzed the computers and the camera that belong to Williams and found child pornography," Jeff Yesensky, FBI special agent, said in a video posted online Monday to bring awareness to the case.
"Because of his status, he has the means and access to children, and that's what makes him dangerous," Yesensky said. "He preys on the most vulnerable children."
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