US woman decapitated son she was allowed to keep

A woman who decapitated her four-year-old son with a kitchen knife showed signs of mental illness nine months before the attack – but child welfare officials decided she was not a serious threat to him.

Lars Sanchez was found dead last month in a bedroom he shared with his mother in Los Angeles.

Nine months earlier, Yolanda Tijerina was seen screaming and shouting “I think you killed my son” outside the boy’s Highland Park preschool. The principal called a child abuse hotline.

Child welfare and mental health officials investigated but the boy was not removed from his home.

Authorities concluded that any risk could be addressed through informal monitoring by relatives and neighbours.