A 21-year-old expectant mother in Cali, Colombia, was lured from her boyfriend's home, stabbed to death, and had her unborn daughter cut from her womb, and authorities say more than four people may be involved in the killing.

María Camila Potosí was eight months pregnant when she was last seen on July 16 riding on the back of a motorcycle in Polvorines, a neighborhood in the southwestern Colombian city of Cali. Her body turned up days later, four miles from her home, wrapped in blankets and bearing multiple stab wounds. Her baby, a girl the family had already named Alahia, was gone.

No arrests have been reported. The baby has not been found. And the city of Cali is now offering a $62,000 reward for information that leads to arrests and to Alahia's recovery, according to Mayor Alejandro Eder's office.

A phone call, a motorcycle, and a missing mother

The trap, as described by Potosí's family, began with a phone call. Potosí was at her boyfriend's family home on July 16 when she received a call from a woman she had met at a Cali center for expectant mothers. She told her family she was going to pick up gifts for the baby. She left on the back of the woman's motorcycle.

She also had an appointment with her obstetrician that day. She never made it.

Her sister, Juliana Meneses, told Univision's news magazine Primer Impacto that the family did not immediately panic. Potosí's boyfriend arrived to pick her up but could not find her.

Meneses told the outlet:

"We thought maybe she was getting her nails done."

By the time police found Potosí's body on Monday, covered in several blankets, stabbed repeatedly, her baby removed, the family's worst fears had been confirmed. Gen. Herbert Benavídez, commander of the Cali Metropolitan Police, said more than four people may have been involved in the kidnapping and killing.

A former boyfriend denies any role

The woman who drove the motorcycle has not been publicly named by authorities. But on Friday, a man named Carlos Rincón posted a video on social media identifying himself as the suspect's former boyfriend. Rincón said his ex-girlfriend had told him in January that she was pregnant.

Rincón said the suspect did not return to his home the night Potosí disappeared. He insisted he had no involvement.

"And many people think I had something to do with it, the kidnapping and murder of the 21-year-old woman, because I had been the motorcyclist's partner."

He added:

"We had nothing to do with it. We knew nothing. My family was another victim. We trusted her, we believed in her."

Rincón also said he had been excited about the suspect's pregnancy. Whether that pregnancy was real, and whether it had any connection to the removal of Potosí's baby, remains unclear. Police have not commented on a possible motive.

A mother's plea for a missing granddaughter

Potosí's mother, Alba Gomez, made a public appeal through Colombian outlet RCN Noticias, begging for the return of baby Alahia.

"The only thing I ask with this appeal and with the hopeful faith I hold that my baby is alive, is for her to be found."

She continued:

"I ask that the people who have her search their hearts and return her to me."

A police spokesperson told the New York Post that the investigation is ongoing and declined to provide further details. No suspects have been named. No charges have been filed. The city's $62,000 reward stands as the primary public tool for generating leads.

Critical questions remain unanswered

The case leaves gaping holes. Authorities have not disclosed the identity of the woman on the motorcycle, nor whether she has been located. They have not said how the baby was removed from Potosí's body, whether the act was crude or surgical. They have not explained how a 21-year-old, eight-months-pregnant woman was lured away from her family in broad daylight by someone she apparently trusted.

Potosí was a first-time mother. She had named her daughter. She had an obstetrician's appointment the same day she vanished. She left to collect baby gifts from a woman she met at a center designed to help expectant mothers.

That a place built to support pregnant women became the setting where a predator found her victim is a detail that needs no editorial comment. It speaks for itself.

Somewhere in Cali, a newborn named Alahia is either alive or she is not. Her grandmother is waiting. The people responsible have not been caught. And a $62,000 reward is all the city has offered so far to change that.

When the authorities finally do catch up to everyone involved, the world will be watching to see whether Colombian justice treats this crime with the gravity it demands.