A federal judge in Billings on Thursday sentenced a Washington man to five years in prison for bringing women to Montana to work as his prostitutes.

U.S. District Judge Susan Watters called the operation run by defendant Andrew Anthony Rivera, 24, of Tacoma, sophisticated. She said Rivera made thousands of dollars off of women he coerced into sex trafficking in various states.

Rivera faced a guideline range of about three years to four years, but Watters followed a prosecution recommendation for a longer sentence.

Although the judge said enhancements for coercion and obstruction had been factored into the guideline range, the range was still too low and did not reflect the harm caused by the crime.

Rivera told the judge he had changed his ways, and that he has a newborn child and no intention of going back to sex trafficking.

Rivera pleaded guilty in May to transportation of a person with the intent to engage in criminal sexual activity. The judge accepted a plea deal and dismissed a second count.

While the two counts involved two different victims, Watters said the investigation showed there were four other women Rivera had groomed to work in commercial sex trafficking and took to multiple states.

Assistant U.S. Attorney Zeno Baucus said earlier that a law enforcement investigation in April 2016 led to online communications with a person who was offering sex for money. Officers went to the Lexington Inn in Billings and a woman, identified as S.B., told them she had traveled from Washington with Rivera to engage in prostitution and he kept most of her earnings.

Rivera showed up at the motel later in the day and was detained, Baucus said.

On Thursday, Baucus recommended a six-year sentence, saying the evidence showed there were at least five victims and that Rivera used physical and emotional abuse to manipulate and groom the women.

Baucus called sex trafficking “an epidemic.”

Assistant Federal Defender Gillian Gosch sought a guideline sentence. While agreeing sex trafficking was an epidemic, Gosch said Rivera was on the streets by about age 12, has a substance abuse problem and was remorseful.

Watters said Rivera merited a longer term in prison. Rivera learned the business from an “old experienced pimp” who went by the initial “V,” she said.

In a search of Rivera’s motel room and vehicle, Watters said, officers found $3,400 on Rivera, another $2,000 in cashier’s checks to Rivera, a stolen handgun, ammunition, notepads from 11 different hotels with the names and phone numbers of customers who had paid S.B., condoms, travel receipts, a laptop, two cell phones and online ads for sex and the rates.

The sex rates ranged from $120 for 20 minutes to $400 for two hours, Watters said.

Rivera also had $5,000 deposited in a local bank, Watters said.

The evidence showed “a fairly sophisticated operation. He was totally in control of the finances,” the judge said.

In addition, Rivera has a domestic violence conviction involving S.B., indicating violence in their relationship was “part of the way he kept S.B. in line,” the judge said.

Rivera also showed a lack of respect for the law and court by violating conditions of his pre-trial release and absconding, prompting a warrant for his arrest, Watters said.