Ronald Felts, 67, was sentenced to 25 years in federal prison Monday for possessing and receiving child pornography which he downloaded from the Internet, according to a release by the U.S. Department of Justice.

During court proceedings, Felts, a former bookkeeper in Hilo, admitted downloading and saving images to computers at his residence, knowing that the images depicted minors engaged in sexually explicit content.

U.S. Attorney Florence Nakakuni said that according to information produced in court, Felts bought access to various websites which offered child pornography and saved images to his home computers or external hard drives.

Federal law enforcement agents executing a search warrant on Felts' Hilo residence recovered two computers and eight external hard drives, which were found to contain approximately 1.7 million pornographic images and approximately 31,000 pornographic videos, the majority of which showed children engaged in sexually explicit conduct, including depictions of prepubescent children under the age of 12.

When the FBI submitted Felts' collection to the National Center for Missing and Exploited Children, it reported that it was the largest personal collection of child pornography that it had ever received.

In pronouncing the sentence, U.S. District Judge David Alan Ezra commented that Felts possessed "incredibly horrific images," and that Felts' possession of child pornography in conjunction with his physical exploitation of a teenage girl represented the "perfect storm" of child sex offenders.

Upon Felts' release from prison, Judge Ezra ordered Felts to register as a sex offender in any state where he lives or works, and to undergo sex offender treatment.

Judge Ezra also sentenced Felts to a five-year term of supervised release.

The case was investigated by the FBI with the assistance of U.S. Immigration and Customs Enforcement's Homeland Security Investigations, and was prosecuted by Assistant U.S. Attorneys Amy Olson and Michael Nammar.