Samantha Fleming was asleep in the Indiana apartment she shared with her boyfriend and newborn daughter when the doorbell rang April 6. On the other side, police say, was a professionally dressed woman carrying a binder who introduced herself to Fleming's boyfriend as a Department of Child Services worker on a surprise visit.

But authorities say the woman, Geraldine R. Jones, never worked for the child-welfare agency and that her visit to Fleming's apartment in Anderson, about 30 miles north of Indianapolis, was part of an elaborate scheme to take the 17-day-old baby and claim the girl as her own.

Why Jones targeted Fleming, and why the young mother and her daughter, Serenity, left the apartment with her, were key questions in a mystery police continued trying to unravel Tuesday. Jones remained in a secure facility in Bedford, Texas, facing charges of kidnapping, criminal confinement and murder following the discovery Friday of Fleming's body in a home in Gary.

Anderson Police Sgt. Chad Boynton said Jones, who was hospitalized for depression and suicidal thoughts, had refused to speak with detectives. Chief Deputy Prosecutor Steve Koester said Jones has waived extradition and is expected to be returned to Madison County by April 30.

Family members of Jones and Fleming didn't return calls seeking comment this week. But a probable cause affidavit released Tuesday shed light into the young mother's disappearance and painted a picture of a suspect who claimed she was pregnant, had furnished a home nursery with baby furniture and baby clothes and had either hosted or been the recipient of a baby shower.

According to the affidavit, Jones, 36, arrived at the apartment Fleming and her boyfriend, Rainey Stanley, shared and identified herself as a child services worker. She told Fleming she needed her to go to Gary for a hearing and said it would look better if she brought Serenity with her.

That was the last time, Stanley told police, that he saw Fleming alive.

Police say they believe Jones targeted Fleming but haven't indicated why she would have masqueraded as a child services worker or how she would have been familiar with Fleming's family situation. Boynton said Fleming had had previous contact with the Department of Child Services, but details weren't available Tuesday. DCS spokesman James Wide declined to comment, citing privacy laws.

Anderson Police Detective Scott Sanderson said that when Fleming didn't return, police began trying to track her cellphone to locate her and the baby. The affidavit said several text messages were sent from Fleming's phone to her mother but that the family didn't believe Fleming sent them because she is a poor speller and the text messages had "perfect spelling."

Gary police found Fleming's wallet in an apartment complex where Jones' sister lived. Sanderson went to Gary to meet with detectives there on Friday and went to Jones' address, where he found a woman who identified herself as Jones' sister holding a baby.

The woman told Sanderson that Jones had dropped the baby off at her father's the previous Friday and that another sister had taken Jones to the airport to go to Texas.

Police say Jones told family members she was pregnant with twins and that one had died at birth. But her sister told police she didn't think the baby belonged to her sister and that she had taken the infant from her father because he is elderly. She said her sister had attempted to commit suicide the day before.

She then mentioned an odor in the house, the affidavit states, and asked Sanderson, "Do you smell the smell in the house? It smells like someone is dead."

Sanderson said he and a Gary police officer traced the smell to a closet, where they found a plastic bin with what appeared to be a body in a garbage bag tied with duct tape.

The body, which had been doused in bleach, was identified as that of Fleming. Police counted at least 10 stab wounds, the affidavit says.

Police said they are trying to determine a motive but the evidence "indicates that Jones intended to raise Serenity as her own child."