Authorities filed charges in a sex-trafficking operation Wednesday in Washington County which they say stretched across the U.S. to ensnare foreign-born women to work as prostitutes for clients who sometimes physically and sexually assaulted them.

Headed by two women described as “boss ladies” based in Irvine, authorities say the enterprise involved transporting women — mainly Chinese nationals — to businesses and private residences scattered around the metro area, including Oakdale, Cottage Grove, St. Paul, Blaine, Maplewood and St. Louis Park.

Women also were sent to more than 20 other states across the country.

Dongzhou Jiang, 28, of Blaine, served as the regional manager for the operation’s Minnesota and North Dakota service area, according to the criminal complaint, coordinating with his bosses in California to transport women advertised for sex on Backpage.com to residences in the Twin Cities.

Part of the ring operated out of the east metro. That’s where Cottage Grove police discovered a house purchased by traffickers that had nothing but two beds and a line of men waiting to have sex, said Washington County Attorney Pete Orput.

Orput’s office headed up the investigation that led to the charges.

Kim Mohr, spokeswoman for the Irvine Police Department, confirmed that local officers assisted in the case but would not elaborate, citing the investigation was led by another department.

The women trafficked were made to work 12 to 14 hours a day and had to pay their traffickers housing fees, transportation costs and hotel expenses and provide their own food, authorities said.

None of them lived in the areas they were sold and some had to give over their passports, authorities said. If they didn’t follow the rules, they risked being fired and feared deportation, authorities said.

Orput said the enterprise appeared to be headquartered in Irvine, where traffickers posted tens of thousands of ads for sexual services on internet sites such as Backpage.com.

Interested buyers from across the country contacted traffickers at the hub and were texted an address of the location nearest them within the ring’s service area, which stretched across 29 states, Orput said.

“It seemed to me that this was the Uber of sex-trafficking … where you could order a human being,” he said.

The investigation involved several law enforcement agencies, including the Washington and Ramsey county attorney’s offices, as well as Woodbury, St. Paul, Oakdale, Cottage Grove and Minneapolis police.

Investigators discovered tens of thousands of dollars in traffickers’ bank accounts, authorities said. One account contained more than $850,000.

Those charged include Jiang; Fangyao Wu, 23, of Irvine; Sophia Wang Navas, 49, of Chino Hills, Calif.; and Hong Nmn Jing, 48, of Irvine.

Each faces six felonies, including racketeering, aiding and abetting in sex trafficking, aiding and abetting in the promotion of prostitution and aiding and abetting a business engaged in the concealment of criminal proceeds.

While describing the prosecutions as a victory in the fight to combat sex trafficking, Orput said agencies still have a lot of work in front of them.

“We would like to stop this entire pipeline … but we have a lot of work to do.”

Both he and Choi emphasized that part of the effort also needs to target and reduce the demand fueling the sex-trafficking market.

“How we raise our boys really matters,” Choi said.

Orput added that the “johns” who pay for sex were engaging in behavior that was not onlycriminal, but also “immoral.”

Authorities are hopeful news of the charges might reach the victims and help convince them to come forward.

Orput noted during the press conference that the majority of the women reached through the investigation were reluctant to work with law enforcement, largely out of fear of the consequences they might face from both immigration officials and their traffickers.

He added that he wasn’t sure how the east metro became so entangled with the enterprise, but said he hoped the criminal charges filed Wednesday would “send a message” to those involved that they won’t get away with it.