According to reports, a four-year-old died after slipping into to a septic tank at a private school in Iyyappanthangal near Porur on Friday. The workers hired by the school to clean a block in the septic tank had left it open and went for tea when Kirtheeswaran, along with three others, went to the toilet. Without noticing the open septic tank, the boy fell into it and others ran to a teacher to inform about the incident. The fire and rescue services personnel arrived and took out the body, reports added.