An 85-year-old woman was allegedly raped in northwest Delhi's Shakurpur area on Friday, police said.
Accused Akash (28) has been arrested in connection with the case, they said.
A senior police officer said an elderly woman reported that she was sexually assaulted by an unknown person in the early hours of the day.
A case under section 376 (rape) of the Indian Penal Code was registered at Subhash Place police station and an investigation was taken up, the officer said.
Earlier in the day, the Delhi Commission for Women (DCW) issued a notice to the city police in connection with the alleged incident.
The 85-year-old victim, who was staying alone in a slum, alleged that a man barged into her living area around 4 am and raped her, the panel said.
"She has also informed that the accused punched her face, cut her lip with a blade and tried to strangulate her.”