Mother 'ate baby's brain' - police (graphic content)

A woman charged with murdering her three-and-a-half-week-old son used a knife and two swords to dismember the child and ate parts of his body, including his brain, before stabbing herself in the torso and slicing her own throat, police in Texas say.

Otty Sanchez, 33, is charged with capital murder in the death of her infant son, Scott Wesley Buchholtz-Sanchez. She is recovering from her wounds at a hospital, and is being held on $US1 million (NZ$1.52 million) bail.

San Antonio police chief William McManus says the attack early on Sunday morning occurred a week after the child's father moved out. Otty Sanchez's sister and her sister's two children, aged five and seven, were in the house, but none were harmed.

Otty Sanchez's aunt, Gloria Sanchez, says her niece has been "in and out" of a psychiatric ward, and the hospital called several months ago looking to check up on her. She did not elaborate on the nature of her niece's health problems.

"Otty didn't mean to do that. She was not in her right mind," a sobbing Gloria Sanchez said. She said her family was devastated.

McManus, who appeared uncomfortable as he addressed reporters, said Sanchez apparently ate the child's brain and some other body parts. She also decapitated the infant, tore off his face and chewed off three of his toes before stabbing herself.

"It's too heinous for me to describe it any further," he said.

McManus described the crime as so grisly police officers barely spoke to each other while looking through the house. Parts of the child were missing, including pieces Sanchez allegedly ate.

"At this particular scene you could have heard a pin drop," McManus said. "No one was speaking. It was about as sombre as it could have been."

Officers called to Sanchez's house about 5am local time on Sunday found her sitting on the couch screaming "I killed my baby! I killed my baby!" McManus said. They found the boy's body in a bedroom.

Police said Sanchez said the devil told her to kill her son and she was hearing voices.

"It was a spontaneous utterance," McManus said.

Police said Sanchez did not have a lawyer, and they declined to identify family members who might speak on her behalf.

No one answered the door on Monday at Sanchez's one-storey home, where the blinds were shut. A hopscotch pattern and red hearts were drawn on the walk leading up to the house.

Authorities said Sanchez and her sister took turns watching the baby on Sunday morning, and the boy was placed in Sanchez's care about 1.30am local time. Her sister discovered what happened about three hours later and called police.

Investigators are looking into whether postpartum depression could have played a role in the attack, McManus said. Authorities said they were looking into Sanchez's mental health history to see if there was anything "significant" but did not elaborate.

- AP