A woman allegedly killed her two-year-old son and set herself ablaze on Monday morning at her residence at the Lakshmi extension in Chikkamagaluru. The police gave the names of the deceased as Mamatha (30) and her son Mallappa. The police said, incident must have happened at about 9 a.m., when her husband Ramesh was not at home. Relatives of the woman told the police that Ms. Mamatha had attempted suicides on a couple of occasions in the past as she was mentally very much disturbed after the death of her first son about child, about three years ago. The Chikkamagaluru Town police have registered a case, following a complaint filed by Mr. Ramesh.