A 15-year-old girl, arrested Wednesday for allegedly killing a five-year-old boy in Khair area of Aligarh, has told police that she killed the boy because his father had raped her two days ago. The boy, son of a labourer, had gone missing Tuesday when he was playing outside his home. On Wednesday morning, the body was found in a vacant plot near his home. It had been wrapped in polythene and there were strangulation marks, police said. The boy’s family accused the girl of murder, claiming she was a drug addict.