GRAPHIC WARNING: Some readers may find the details in this story disturbing.

Three people have been arrested in connection with the death of a pregnant Chicago woman, who was strangled before her baby was cut from her womb.

Chicago police took the three into custody shortly before the body of Marlen Ochoa-Lopez was discovered behind a home on the city's Southwest Side.

Ochoa-Lopez was nine months pregnant when she disappeared April 23. Police and family say she had gone to a home in response to a Facebook offer of free baby clothes.

Authorities say that the same day Ochoa-Lopez vanished, a 46-year-old woman called 911 about a baby in distress. The baby wasn't expected to survive.