Local police officers had claimed the cremation was carried out "as per the wishes of the family".
The National Commission for Women (NCW) on Thursday sought an explanation from the Uttar Pradesh Police on the urgency to cremate the body of the Hathras gangrape victim in the middle of the night in the absence of her family members.
The Dalit woman was allegedly raped at a village in Hathras by four men on September 14, and she died on Tuesday at Delhi's Safdarjung Hospital.
Her body was cremated in the early hours of Wednesday, with her family alleging that the local police forced them to conduct the last rites in the dead of the night.
Local police officers, however, told PTI the cremation was carried out "as per the wishes of the family".
The NCW, in a statement, said it is shocked at the brutal gangrape of a 20-year-old woman in Hathras, Uttar Pradesh who died in Delhi after fighting for life for two weeks.
The incident underlines the grim state of women in the society, it said.
The commission said it also came across a disturbing report on police officials cremating her body in the middle of the night without the permission and presence of her family members.
It has been reported that the victim''s body was cremated at 2:30 am by the police without the presence of any family member.
"The victim''s family had reportedly appealed to the District Magistrate for taking her body home for performing the last rites, however the police went ahead with the cremation while most of her family members were away," it said.
"The commission has now written to Director General of Police, Uttar Pradesh seeking an explanation on the urgency to cremate the body of the victim in the middle of the night that too in the absence of her family. NCW has asked the administration to send a reply on the same at the earliest," it said.
As the news of the victim''s death spread, protests broke out in Delhi as well as in Hathras with all sections of society, including politicians, sports, cine stars, and activists expressing anguish and demanding justice for her.