RIVERSIDE (CBS)  — An Orange County man who used social networking sites to meet young girls and photograph them nude, leading to sex acts with one child, was sentenced Wednesday to 100 years in prison.

Joshua David Threlkeld, 35, was convicted March 14 of 79 felony charges, including kidnapping to commit lewd acts on a minor, multiple counts of lewd acts on a child, distributing material with the intent to seduce a child and communicating with a minor with criminal intent, and a misdemeanor count of indecent exposure.

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Riverside County Superior Court Judge Edward Webster imposed the sentence required by law.

The complaint named 50 victims, though prosecutors believe the actual number was in excess of 100.

According to court documents, Threlkeld targeted girls between 11 and 17 years old, contacting most of them between August 2007 and the winter of 2009.

Prosecutors said the defendant posed as a 13-year-old girl, “Sara Miller,” to initiate communication with the girls, most of whom he met via MySpace and Facebook, some from as far away as London, England.

He would purport that “Sara” was sometimes paid to pose nude for a photographer named “Josh” at “Model 508 Studios,” according to Deputy District Attorney Melissa Moore.

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After establishing a rapport with the girls, Threlkeld would attempt to talk them into modeling nude for him or sending him nude photographs of themselves, according to the prosecutor.

She said some girls turned him down flat, while others expressed an interest, leading to face-to-face encounters between the defendant and his victims. Most of the girls who met him were from Corona, Hemet, Moreno Valley, Palm Springs, Romoland and Winchester.

Threlkeld set up photography sessions at his Orange home, in San Jacinto and in Palm Springs, Moore said. On some occasions, he would arrange for two girls to meet him.

The defendant would have the victims disrobe and then interact with one another in sexually suggestive ways while he snapped pictures, Moore said.

A 13-year-old girl, identified in court documents as Vanessa, met with Threlkeld in the summer of 2008 for a photo shoot at a Palm Springs hotel, where she said the defendant sexually assaulted her and paid her $120 afterward.

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