Updated

A Houston-area man was sentenced to 30 years in prison Monday for forcing his daughter into prostitution.

The man was sentenced in Harris County after pleading guilty to aggravated compelling of prostitution. He was arrested in June 2015 following an undercover investigation by the Houston Police Department’s Vice Division and the FBI, part of Houston’s Child Exploitation Task Force.

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“It’s believing in her (the daughter), and then building a case with evidence that supports her story, if it does,” said JoAnne Musick, chief of Harris County District Attorney’s Office of Sex Crimes Division.

Fox News will not identify the man to protect the identity of his daughter, a victim of a sex crime.

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The National Center for Missing and Exploited Children received the initial tip that the man was prostituting his daughter. They also learned that the father was advertising his daughter on BackPage.com. They passed all the information along to the Child Exploitation Task Force.

Once the authorities were able to locate the girl on Back Page they set up a prostitution date to recover the child, according to Musick.

The father began by bringing his daughter to truck stops and had her knock on doors and proposition them for sex. According to Musick, when he saw that it was lucrative, he began to advertise.

Musick said the girl didn’t have a way to speak up because her father was the only person she had and her estranged mother had recently died. She helped the police build the case against her father from day one.

“She was able to give the police a lot of details and they were able to trace them down and substantiate them. A lot of times with these kinds of cases with back page and other things like that, you have a lot of digital evidence. So we can subpoena some of that from back page and we download other information from other devices,” said Musick.

Musick explained that authorities can recover information from cell phones and other devices that many users think is deleted. This included conversations between the daughter, father and customers.

The daughter said she had multiple customers a night and her father kept the money. She said when her father found out she was sexually active, he said if she was going to act like a prostitute she might as well be one. The crime went on for several months.

Authorities were able to find relatives of the girl who took her in. She was placed into counseling and according to Musick, she is still traumatized but doing much better.