The daughter of two New York University professors who may have been murdered last week in her mother’s home had been “trying to get away” from her ex-boyfriend, a family member said yesterday.

Police sources said authorities apprehended the ex-boyfriend, Michael Cordero, 23, last night in order to question him about the death of Boitumelo McCallum.

He was found at West 62nd Street and West End Avenue, near the Amsterdam Houses in Manhattan. Police sources said they believed Mr. Cordero had tried to kill himself and had been taken to Roosevelt Hospital.

Family members of the 20-year-old victim said they last saw McCallum at a jovial family dinner last Wednesday evening. Her father, Robert McCallum, and her father’s wife, Cindy Maguire, both adjunct professors at NYU, and her younger brother were leaving for a vacation in South Africa the next day.

The family said police have told them that Mr. Cordero is the primary suspect in the murder — and they say they’re not surprised.

The mother of McCallum’s stepmother, Patricia Maguire, who attended the dinner on Wednesday, said the police “suspect the boyfriend. They had broken up some time ago and she was very much trying to get away.”

After the dinner, McCallum returned to her mother’s apartment in NYU faculty housing at 4 Washington Square Village, where she was living with two subletters while her mother was away in South Africa for the summer.

“That’s when we said goodbye,” Ms. Maguire said.

Police said McCallum hosted a party later Wednesday night that lasted until early Thursday morning.

She was last seen Thursday, Police Commissioner Raymond Kelly said.

Neighbors found her body wrapped in a sheet and tucked between the bed and the wall in her locked bedroom three days later, after noticing a smell coming from the room.

The commissioner yesterday disputed reports that debris including liquor bottles and condoms had been found in the room. He said the medical examiner had yet to determine the cause of death, but that police are investigating it as a homicide.

McCallum had injuries to her face, including a fractured nose, Mr. Kelly said.

McCallum’s father and mother, Teboho Moja, who are divorced, spent yesterday trying to fly back to New York from South Africa, where they both were traveling when the incident occurred.

Ms. Maguire said McCallum, known as “Tumi” to her friends and family, had been very close with her father.

“She was just a lovely person,” Ms. Maguire said. “She made friends everywhere.”

McCallum was born in South Africa, where both her parents are from, and grew up in New York City. She was planning to go back to Mills College in Oakland in two weeks, where she would have been a junior, Ms. Maguire said.

A friend of McCallum’s from college who lives in TriBeCa, Lily, 21, described the victim as “compassionate, delightful, and graceful.” She said McCallum loved dancing and Michael Jackson.

“It’s just such a horrible way for her to die. For anyone to die,” she said. “I can’t imagine how her mother must feel.”