An investigation into a Tennessee man accused of recording himself raping unconscious boys has shown there "could be a decade of victims," a police spokesperson told CNN.

Camilo Hurtado Campos, 63, is being held in Franklin, Tennessee, on charges of rape of a child and sexual exploitation of a minor. The arrest came after he left his phone at a restaurant and employees found "dozens of unconscionable videos and pictures of children" on the device while trying to determine its owner, Franklin police said Sunday.

Police said Campos "recorded himself raping unconscious boys," and that evidence of the rapes of at least 10 children -- appearing to be approximately 9 to 17 years old -- was found on the phone. Investigators have identified three of the recorded victims, Franklin police said.

In addition to those 10, five other people have come forward to say they were victims, Franklin police said Monday.

And "people who were victims in some of the recordings that have come forward are in their 20s now," Franklin police Lt. Charles Warner told CNN Tuesday.

"If you do the math, there could be a decade of victims that we don't know about," Warner said. He noted Campos has lived in the Franklin area for about 20 years.

Additional charges are expected to be filed, police said.

Investigators are sifting through hundreds of photos and videos found on Campos' phone, Warner told CNN.

The victims who have been identified are male, and most of them are Hispanic, according to the lieutenant.

"There are undoubtedly more (victims)," Warner said. "We are in the infancy of this investigation, and this could be the tip of the iceberg."

Police initially reported that Campos was a "popular soccer coach," but Warner said the suspect's affiliation with local soccer teams is "ambiguous" and investigators have not been able to confirm he worked as a coach at local schools or organized soccer leagues.

Investigators believe Campos approached his victims near parks or soccer fields and told them he was a coach who wanted to recruit them, according to police.

"We know that he used the guise of the fact that he was a soccer coach ... and that's how he would befriend them," Warner said.

Police intend to work closely with victims and their families to process the "terrible chain of events" and reach some closure, Warner said.

"The people that are coming forward have felt such shame, such terror, and it's very hard, I'm sure, to remember and process something so traumatic that happened to you, whether it was yesterday or whether it was 10 years ago," he said.

Campos' bond has been set at $525,000, a spokesperson for the Williamson County Sheriff's Office said. The county clerk told CNN Tuesday that an attorney had not yet been listed for Campos.

Campos is expected in court on July 25.

Police urge families to speak to children and come forward

Warner implored families to speak to their children and contact police if they believe their child has had any affiliation with Campos.

Police say they believe Campos drugged his victims. Because of that, children may not know they are a victim even if they have been to Campos' home, Warner said.

"The combination of drugs that he was using ... was so powerful and so potent that he undoubtedly knew what he was doing, because he was able to render these children into an unbelievably unconscious state," Warner said.

Police said some victims told them they didn't come forward earlier because they believed it would be expensive for them to do so.

"That is heartbreaking for us, that there is that disconnect in the community," Warner said.

"We are there to serve victims of crime, and it doesn't cost them anything," Warner said. "We want people to know that our services are without limit and without obligation, and you can come to us."