KATHMANDU: Police on Thursday arrested an 18-year-old girl on the charge of killing her newborn son, in Takhel, Bajrabarahi Municipality-11 of Lalitpur. The girl, who hails from Irkhu-7 of Sindhupalchok, strangled her newborn and dumped the body in a water tank inside her toilet on Wednesday, police claimed. Further investigation is underway.