BIDDEFORD — A Biddeford man accused of transporting a woman from Maine to New Hampshire to prostitute her changed his plea to guilty Tuesday at U.S. District Court in Portland.

Leo Grondin, 49, has been charged with transporting an individual in interstate commerce with the intent that she engage in prostitution. Grondin pleaded not guilty to the felony charge at his arraignment on Sept. 1, and a trial had been scheduled for next Monday.

After determining that Grondin made the decision to reverse his plea knowingly and voluntarily, Judge Nancy Torresen accepted the plea reversal Tuesday, as a thickbearded Grondin appeared in court wearing an orange prison jumpsuit.

Grondin faces up to 10 years in federal prison and a fine of up to $250,000, as well as between five years and life of supervised release following imprisonment, according to Torresen. Assistant United States Attorney Julia Lipez, who is prosecuting the case, said the prosecution may also seek restitution for the victim.

Grondin, who allegedly pimped his girlfriend, a woman in her late 50s, and other women through online advertisements, was arrested in July and indicted last month on the interstate pimping charge.

According to court documents, police began investigating Grondin in June, after finding his phone number on websites known to advertise sexual services. Shortly after, Biddeford police received a tip from the daughter of the woman in her 50s, who said she found messages about prostitution on her mother’s cell phone, and that when confronted, her mother admitted Grondin was prostituting her and other women, court documents state.

On July 17, police located Grondin and the mother in a hotel room in Dover, New Hampshire, and Grondin was arrested on a New Hampshire warrant.

According to court documents, the woman later told police that she met Grondin about a year ago, and he harassed her until she agreed to work as a prostitute for him. She also told police that Grondin would take her across state lines for prostitution, that he would always keep all of the money she made, and that he would sometimes become physically abusive when she refused to engage in prostitution.

Torresen said she will now review the sentencing guidelines for the offense, before the court schedules a sentencing hearing.

Grondin’s attorney, Neal Stillman, estimated that it would be at least a month or two before Grondin is sentenced. He will remain in federal custody until then.

— Staff Writer Angelo J. Verzoni can be contacted at 282-1535, ext. 329 or [email protected].