Updated

Detectives and worried relatives are searching desperately for a cold-hearted killer who murdered an 8-months-pregnant Massachusetts mom, cut her uterus open and took her nearly full-term baby girl.

The decomposing body of 23-year-old Darlene Haynes was found wrapped in a blanket and dumped in a closet in her apartment in Worcester.

Her landlord was checking on a report of a strong odor coming from the premises on Monday when he discovered the body, which was so mutilated that police said they couldn't immediately determine its gender.

“We want our baby back,” a woman who identified herself as Haynes' aunt told the Boston Herald. “We want our grandchild back, and we want to know why.”

Haynes' longtime boyfriend, 24-year-old Roberto Rodriguez, is due in court Wednesday on charges he assaulted Haynes in a previous incident, according to the Worcester Telegram & Gazette.

Rodriguez is charged with aggravated assault and battery and intimidation of a witness. He is not named as a suspect in Haynes’ murder.

The hearing stems from a June 24 incident in which Haynes accused him of shoving her into a glass table and disconnecting the phone to prevent her from calling police.

Haynes had an active restraining order against Rodriguez, the Telegram & Gazette said.

Haynes was last seen alive on July 23. Autopsy results on Tuesday revealed that the fetus that was cut out of her womb was female. Police say the baby could survive but would need medical attention immediately.

Det. Captain Edward McGinn Jr. told the Telegram that Haynes suffered head injuries in the attack. The medical examiner ruled Haynes' death a homicide, but the exact cause won't be known until toxicology tests are complete.

Haynes' aunt, Sandra Grandmaison, told the Herald she last talked to her niece two weeks ago. She said she was a troubled young woman who never graduated from high school or developed mentally.

“She was a very sad, very young girl who never really grew up,” said Grandmaison, 58. “Darlene does not have the know-how or the ability to sense danger.”

Anyone with information on the case or the whereabouts of the baby is urged to call Worcester detectives at (508) 799-8651.

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Read more at the Worcester Telegram.

The Associated Press contributed to this report.