The victims (both of them) throat was cut so deep that it was almost separated from the torso. There was no indication of a puposeful intention to cut a perticular blood vein and there was no specific effort for that alone. A butcher's knife or a Khurki used by nepalese might have been used according to the forensic experts. It was single deep cut by heavy but sharp knife. Killers brought a knife because , a revolver for example would make a terrific noise. A 4 inch width ,8 inch long heavy weapon was used to bang the head of the victims so much so that the skull broke and caved in . This is generally done by the killers when the intention was to silence the victim in sleep or kill them so that victim can not shout or cry. There was no forced entry in to the girl's room which means either it was open or she opened it to a known person(s). But the way her dead body was lying tells that she was sleeping ,which means she did not not lock the door when slept. All this points to servants friends, and persons known to him. Even if killers are Dr.Talwar's friends or relatives with a purpose of honour killing, they would not likely have drinks with him in a servants room. Allowing a servant to live inside the house means he has been a very trusted servant. Surprisingly they do not have a dog.