HONOLULU (KHON2) — A former teacher accused of distributing child pornography will remain in custody as he waits to go on trial. Prosecutors said Alden Bunag is a danger to the community and the judge agreed.

Authorities said there are many challenges in catching suspects in cases where children are victimized, but law enforcement officers have some key tools to go after them.

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Court records said Bunag sent child pornography to a teacher in Philadelphia, and admitted to having sex with a 13-year-old boy who was a former student.

Federal agents arrested Bunag last week, but the state attorney general also has the Hawaii Internet Crimes Against Children Task Force that goes after such predators.

“Most of the time, they do not have a criminal record. So it’s not like there’s anything that would lead us to go after them,” said Special Agent Edward Arias, commander of the task force.

Arias says that presents a lot of challenges because law enforcement has to cast a wide net. But they get cybertips from social media companies like Facebook and Tik Tok, as well as internet providers. Court records said a cybertip led to the arrest of the teacher in Philadelphia, which then led to Bunag’s arrest.

Records say Bunag’s videos had been encrypted but officials were able to open them up anyway.

“We’ve done a lot of cases where the bad guy thinks I’m just gonna delete it or I’m gonna encrypt it, no one‘s ever going to see it,” said Arias. “And they get shocked when we un-encrypt and un-hide all the files.”

He said another tool, to get more information from a suspect, is what’s known as tactical polygraph or lie detector test.

“A lot of them, because they want to prove their innocence, will agree to it and halfway through the polygraph, they’ll admit yes, I’ve touched other kids in the past,” said Arias.

It’s a disturbing trend but Arias said victims are getting younger, mainly because children are getting more used to using cell phones and computers.

“Younger and younger kids are getting cell phones,” said Arias. “You can’t go to school these days without having a computer, you have to have a computer.”

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His advice to parents is to keep communicating with their children. And if they suspect something wrong with their behavior, there are agencies out there that can help.