Officers on Sunday responded to a hospital on South Grand Avenue and launched an investigation into the death of the baby, according to the Los Angeles Police Department. The child had been taken to hospital by their mother before staff there called police, but it's unclear what prompted that.
The Los Angeles County Medical Examiner's Office has not determined the cause of death.
As a result of the investigation, the child's biological parents, Annabell Porcayo and Jaime Lopez, were arrested.
Two other children of the same parents were also taken into protective custody, but additional details were not available.