A woman has pleaded guilty to federal charges in connection with a sex trafficking operation that stretched from China to Maine.

Derong Miao appeared in U.S. District Court in Portland on Tuesday. She and her husband, Shou Chao Li, were both indicted on a host of charges in 2018. Among other things, Miao admitted that she and her husband rented two properties in Portland that were used for commercial sex, and she helped organize the transportation of four separate women between New Hampshire and Maine for prostitution.

She pleaded guilty to one count of conspiracy to engage in interstate transportation and travel for prostitution, as well as four counts of interstate transportation for prostitution. She also agreed to forfeit $2,000 to the federal government. The prosecutor agreed to dismiss two counts of sex trafficking by fraud or coercion, and one count of interstate transportation for prostitution.

A sentencing hearing has not yet been scheduled, but Miao agreed not to appeal any sentence that is less than four years and nine months. The conspiracy charge carries a possible penalty of five years in prison; the interstate transportation charges, up to 10 years each.

Miao is a Chinese citizen, and her conviction could have implications on her residency in the United States. She was 37 years old when she was arrested in 2018. Court documents filed so far contain few other details about her life, but the sentencing could bring forth other facts about her.

Li still faces the same charges, plus one count of possessing a victim’s passport as part of the trafficking scheme. He has not pleaded guilty, and his case could go to trial as soon as August. His lawyer did not respond to an email or a voicemail Tuesday.

Attorney Jeffrey Langholtz, who represented Miao, did not answer a question about whether she would testify against her husband at a trial and said after the hearing that he did not have any comment on the case.

Both Miao and Li have been in federal custody since their arrests. Miao, who is held at the Cumberland County Jail, stood quietly next to her attorney during the hearing. U.S. District Judge D. Brock Hornby asked her a series of questions, including whether she received translated copies of the documents in her case and whether she understood her right to a trial. Miao answered through a Chinese interpreter, saying, “Yes, your honor,” and “I understand, your honor.”

Court documents do not identify any of the women who were exploited as part of the trafficking operation or say what happened to them after Miao and Li were arrested. None attended the court hearing. Assistant U.S. Attorney Darcie McElwee said after the hearing that she could not answer questions from a reporter, including one about what happened to the women.

A 2015 assessment published by the Maine Sex Trafficking and Exploitation Network estimated that there are 300 to 400 victims of sex trafficking in Maine every year.

As part of her plea agreement, Miao agreed not to contest certain facts in a narrative filed last week by the government. That document mentions other conspirators but names only Li, and it describes activities that took place in 2016 and 2017.

The government says Miao and her husband were living in New Hampshire when they participated in the trafficking scheme. They leased four residential properties, including two in Portland, that were used for prostitution. Miao allegedly used a social media platform called WeChat to talk to Chinese women about engaging in prostitution in New Hampshire and Maine. The document says the women had mostly come to the United States on visas that did not legally allow them to work, and they hoped to find other jobs but were unable to repay debts associated with their travel. They spoke little or no English and had no other contacts in Maine or neighboring states.

The government says Miao and her husband “benefited financially” from the scheme, and they also made payments to unnamed conspirators. Miao helped with transportation and other logistics needed to bring the women to New England from other states, and she and her husband allegedly moved the women between hotels in the Portland area to avoid detection. Miao also stayed in contact with the women through WeChat “about location changes and the collection of prostitution proceeds.” The document ties her to four separate women.

“Beginning on about August 18, 2016, and continuing until at least October 30, 2017, on at least 33 occasions, the defendant and her husband leased, rented, or agreed to pay for the cost of identified locations (houses of prostitution or hotel rooms) in Maine, New Hampshire, and Vermont where identified Chinese females were actual or registered guests,” the document says.

Langholtz told the judge Miao did not remember the exact number of occasions, but she believed it to be less than 33. The attorneys said they agreed to disagree on that point in the record.