Richard Finkbiner, who lives in the western Indiana community of Brazil, signed an agreement filed in federal court in Terre Haute on Wednesday in which he will plead guilty to child exploitation, extortion and possession of child pornography in exchange for a recommended sentence of 30 to 50 years in prison.

U.S. Attorney Joe Hogsett previously said that his office intended to seek an effective life sentence if a jury convicted Finkbiner.

"From the outset, our focus in this case has been on fully investigating this alleged criminal activity so that we can provide closure - and justice - for the hundreds of potential victims affected by the defendant." Hogsett said during a news conference Thursday in Terre Haute.

According to prosecutors, Finkbiner met most or all of his victims on a video chat website, omegle.com, which offers users random, anonymous one-on-one chats with strangers. The site says it is not for use by children under 13 or older teens younger than 18 without permission of a parent or guardian.

Prosecutors say the teens thought they were looking at live images of people — including a couple, in at least one instance — who were acting sexually and encouraging the teens to do the same, but the images were actually recordings Finkbiner was showing them. He would later contact the teens again and threaten to upload the explicit images he recorded of them to porn websites unless they made more videos for his private use, prosecutors say.

"So u wanna play or b a famous gay porn star?" Finkbiner allegedly asked a Michigan boy.

The alleged victims ranged in age from 12 to 16, and prosecutors say they lived in eight states — Indiana, West Virginia, Iowa, Wisconsin, Ohio, New York, Michigan, Illinois and Colorado.

During questioning by FBI agents, Finkbiner estimated that he had coerced at least 100 young people into making explicit videos, according to court documents. Officials haven't said whether they believe Finkbiner shared the images with anyone.

Prosecutors say the case is an example of "sextortion," a crime that authorities are seeing with greater frequency in which Internet predators catch victims in embarrassing situations online and threaten to expose them unless they create sexually explicit photos or videos. Hogsett has said that Finkbiner's could be the largest case of its kind prosecuted in the U.S.

Michelle Collins, the vice president of the National Center for Missing and Exploited Children's exploited children division, said sextortionists routinely trawl Facebook and other websites searching for embarrassing photos that they can use to blackmail victims.

"It's certainly becoming more of a trend as people share more images online," Collins said.