New Delhi, Feb 14 : A nonagenarian woman was allegedly beaten to death by her 30-year-old grandson in Delhi's Rohini area, said an official on Tuesday. The incident occurred on Sunday. The deceased has been identified as Raisa (90), a resident of Prem Nagar in Rohini, said the official, adding that her grandson, Shahrukh has been arrested by the police. According to a senior police official, on Sunday a police control room (PCR) call was received at Prem Nagar police station regarding a murder following which a police team was dispatched for the spot. "On spot, Raisa was found dead lying in a room. The crime team was called at the place of occurrence and exhibits were collected. On the prima-facie examination of the body, no external injury was seen on the body of the deceased," said the official. "The dead body was preserved in the mortuary of SGM Hospital. On the basis of the statement given by Raisa's son and following the opinion of the doctors after autopsy a case under section 302 (murder), 323 (voluntarily causing hurt) and 506 (criminal intimidation) of the Indian Penal Code has been registered and Shahrukh has been arrested in the matter," said the official. "Further investigation is underway," the official added. /IANS