LAWRENCE, MA — www.eagletribune.com- Melissa Halstrom admitted to police she was running an escort service out of her North Andover apartment, but said she didn’t realize the girls she employed were underage, according to audio recordings played yesterday in Superior Court.

Prosecutors are calling it a confession. Halstrom’s attorney has tried to have it blocked from becoming evidence in her trial.

In the tapes, the then-32-year-old Halstrom first tells North Andover police Sgt. Diane Heffernan that she did not let a 16-year-old runaway from Maine into her escort business because “she looked extremely young.”

But Halstrom changed her story minutes later.

“She has done one or two (appointments), but I did not know she was underage,” Halstrom said in the interview, which came after she was arrested on Sept. 7, 2007.

Prosecutor Kate MacDougall played the tape yesterday for the jury in what will likely be the only time they hear Halstrom’s version of events in this trial. Halstrom is not expected to testify today.

Halstrom, now 34, has been charged with running an underage prostitution ring out of her home in the summer of 2007 along with a business associate, Millbury resident Anthony Gorgoglione Jr. Yesterday was the fourth day of testimony in their trial.

Police said Halstrom recruited her ex-boyfriend’s 17-year-old daughter and two of that girl’s friends into prostitution, gave them Klonopin pills, and set them up on $300-an-hour sex sessions in hotels with older men. Gorgoglione is accused of photographing the three teens in Halstrom’s lingerie and posting the photos on a Web site — the now defunct angelicdelights.net — as a way to advertise the operation.

The 16-year-old runaway from Maine, who used the name Stephanie during jobs, first tipped off detectives to Halstrom’s alleged sex-for-money operation when she surrendered to police, wanting to return home.

Heffernan testified yesterday that detectives found business cards for “Angelic Delights,” notebooks full of appointments labeled “Sasha” and “Alicia” — two of the alleged underage prostitutes. She testified police also found two cell phones that constantly rang as they searched Halstrom’s apartment on the day of her arrest.

“The cell phones were ringing off the wall,” Heffernan said.

Heffernan said she finally picked up one of the phones and answered it. She said the man on the other end was “asking for a particular girl.” Heffernan said she then drove back to the North Andover police station to question Halstrom.

In the audiotapes, Halstrom said she had been an escort for about eight years on and off — in North Carolina and then New York, before finally landing in North Andover.

She was going by the name Angel Marie with her clients, but called herself Brittany back in her New York escort days, she said in the tapes. Halstrom said in the interview that she lived in the apartment in an old, white Colonial mansion off Elm Street for two years.

In the tapes, Halstrom first denied her business was about sex when she being told she was charged with running an underage prostitution ring.

“They are not asked to have sex in exchange for money, and I do not profit from them in any way,” Halstrom said emphatically in the recording.

Later in the interview, however, she talked about the girls making $200 per appointment. She said another $100 went to paying for hotel rooms. When questioned about the amount of lingerie in her apartment, Halstrom answered, “I have a lingerie fetish, as well as a shoe fetish.”

Halstrom told Heffernan her ex-boyfriend’s daughter asked to be an escort.

“She knew what I was doing. We got to talking about it one day,” Halstrom said in the recording. “I told her I did Internet porn to begin with. She didn’t buy it. So I told her I was an escort.”

Defense attorney John Morris tried unsuccessfully to block Halstrom’s statements to police from the trial, saying that Heffernan did not read Halstrom her Miranda rights on the audiotape. Heffernan said she read the rights before the taping began.

“We have no way of knowing what you said,” Morris argued.

Testimony is expected to end this morning, followed by closing arguments. The jury will then begin deliberations.

At one point during Halstrom’s police station interview, Heffernan asked if she was looking for more escorts. Her Web site had a section titled, “Employment Opportunities.”

“I wasn’t looking for girls. The way the phone was ringing I couldn’t handle it anymore,” she said before letting out a laugh. “No, I wasn’t looking for more.”