A federal judge Thursday sentenced a former Casper resident to seven years of imprisonment for crossing state lines to engage in illicit sex.

Leif Bjorn Jourgensen heard the sentence handed down by U.S. District Court Judge Alan Johnson in Cheyenne, according to minutes of the hearing.

Johnson also ordered Jourgensen to cognitive/behavioral treatment, a mental health evaluation, a 500-hour residential drug treatment program, and compliance with sex offender guidelines.

Jourgensen also will be placed on 10 years of supervised probation after his release from prison.

On Jan. 8, he pleaded guilty to a count of interstate travel to engage in illicit sex.

In exchange for Jourgensen’s plea, federal prosecutors agreed to dismiss a charge of attempted enticement of a girl under 18 for sexual activity.

If the case had gone to trial and he was convicted, he could have been sentenced to up to 30 years imprisonment.

The case started April 14 when a male Wyoming Division of Criminal Investigation agent was monitoring public online classifieds websites and found an advertisement from Jourgensen seeking a young girl for sex.

The agent responded, posing as a girl. Jourgensen, who was living in Fort Collins, Colo., responded saying he would pay her $400.

Jourgensen sent the agent a picture of himself, which corresponded to the photo on his Colorado driver’s license.

Further conversations ensued. Jourgensen called a number that was forwarded to a female Homeland Security Agent, who posed as a 14-year-old girl.

They set up a time and a location at a store parking lot in Cheyenne.

Jourgensen drove his pickup to the store, and an agent parked behind his pickup to prevent him from backing up. Agents approached pickup and asked to see his hands.

He drove away, leading law enforcement on a chase to the Frontier Refinery where got a ride to a restaurant, and used the restaurant's phone to make a call.

Agents traced the number to a business in northern Colorado, and Jourgensen was arrested soon after that.