A Lewiston woman and an Auburn man pleaded guilty Wednesday to driving a 13-year-old runaway girl from Lisbon around Massachusetts and Maine for prostitution.

Shawna Calhoun, 24, and Alvin Houston Jr., 27, pleaded guilty in U.S. District Court. Each faces up to 10 years in prison and a $250,000 fine if convicted of interstate transportation of an individual with the intent to engage the person in prostitution.

According to an affidavit, the girl ran away with Calhoun on Dec. 21 and her mother contacted local police. By tracing ongoing phone calls from the girl to her mother, police tracked her movements, which included time in Boston.

Officials said Calhoun and Houston drove the girl to various Boston hotels to engage in prostitution, through ads in the free online classifieds backpage.com, and officials set up a sting in a Bangor hotel.

On New Year’s Eve, Calhoun and Houston drove the girl to a Bangor hotel for what they thought was a meeting with a client. Calhoun and Houston were arrested in the parking lot, where they were waiting in a rental car, according to the affidavit.

The girl, who was not arrested or charged, was released to her mother about 5:30 a.m. Jan. 1, according to the affidavit.

Lisbon and Bangor police worked with the FBI, the Homeland Security Investigations Human Trafficking Task Force and the Maine Drug Enforcement Agency.