The scene was so gruesome investigators could barely speak: A 3 1/2-week-old boy lay dismembered in the bedroom of a single-story house, three of his tiny toes chewed off, his face torn away, his head severed and his brains ripped out.

"At this particular scene you could have heard a pin drop," San Antonio Police Chief William McManus said Monday. "No one was speaking. It was about as somber as it could have been."

Officers called to the home early Sunday found the boy's mother, Otty Sanchez, sitting on the couch with a self-inflicted wound to her chest and her throat partially slashed, screaming "I killed my baby! I killed my baby!" police said. She told officers the devil made her do it, police said.

Sanchez, 33, apparently ate the child's brain and some other body parts before stabbing herself, McManus said.

"It's too heinous for me to describe it any further," McManus told reporters.

Sanchez is charged with capital murder in the death of her son, Scott Wesley Buccholtz-Sanchez. She was being treated Monday at a hospital, and was being held on $1 million bail.

'In and out' of psychiatric ward

The slaying occurred a week after the child's father moved out, McManus said. Otty Sanchez's sister and her sister's two children, ages 5 and 7, were in the house, but none were harmed.

Police said Sanchez did not have an attorney, and they declined to identify family members.

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

Sanchez's aunt, Gloria Sanchez, said her niece had been "in and out" of a psychiatric ward but did not say where she was treated or why. She said a hospital called several months ago to check up on her.

"Otty didn't mean to do that. She was not in her right mind," a sobbing Gloria Sanchez told The Associated Press on Monday by phone. She said her family was devastated.

Investigators are looking into Sanchez's mental health history to see if there was anything "significant," and whether postpartum difficulties could have factored into the attack, McManus said.

Postpartum depression — a pattern?

Postpartum depression and psychosis have been cited as contributing factors in several other cases in Texas in recent years in which mothers killed their children.

Andrea Yates drowned her five children in her Houston-area home 2001, saying she believed Satan was inside her and trying to save them from hell. Her attorneys said she had been suffering from severe postpartum psychosis, and a jury found Yates not guilty by reason of insanity in 2006.

In 2004, Dena Schlosser killed her 10-month-old in her Plano home by slicing off the baby's arms. She was found not guilty of reason by insanity, after testifying that she killed the baby because she wanted to give her to God.

Sanchez's neighbors expressed sorrow and horror Monday at the grisly killing.

Neighbor Luis Yanez, 23, said his kids went to school with one of the small children who lived at the house. He said he often saw a woman playing outside with the children but didn't know whether it was Otty.

"Why would you do that to your baby?" said Yanez, a tire technician. "It brings chills to you. They can't defend themselves."

Allen Taylor, another neighbor, said "once she gets back in her right mind, she's going to be devastated."