The National Human Rights Commission took cognisance of the encounter killings of the four accused in the Hyderabad gangrape-and-murder case and ordered an inquiry on Friday.
The apex human rights body in the country said the encounter was a matter of concern and needed to be probed carefully.
"The commission is of the opinion that this matter is required to be probed very carefully. Accordingly, it has asked its Director General (Investigation) to immediately send a team for a fact-finding, on-the-spot investigation into the matter," the NHRC said.
The team from the investigation division of the commission, headed by a senior superintendent of police, was expected to leave for Hyderabad immediately and submit its report at the earliest, the commission said.
The incident clearly indicated that the police personnel were not "properly alert" and "prepared for any untoward activity by the accused on the spot", which resulted in the death of all four, it added.
Pointing out that the deceased was arrested by the police during investigation and a judgment was yet to be pronounced, the rights body said if the arrested persons were actually guilty, they were to be punished in accordance with law.
The NHRC had earlier said there was an absence of a "Standard Operating Procedure" for the police to immediately respond to panic situations.
"The commission has been insisting upon all law-enforcing agencies to keep the human rights angle in their view while dealing with the persons arrested by them or being kept in their custody.
"The right to life and equality before law are the basic human rights recognised and granted by the Constitution of India," it said.
Acknowledging that the growing incidents of sexual assault and violence against women had created an atmosphere of fear and anger among the public, the NHRC said loss of human lives, even of a person arrested by the police, in such circumstances would definitely give a wrong message to the society.
The commission said it had already taken cognisance of the increasing cases of rape and sexual assault on women across the country and sought a detailed report from all the state governments and police heads as well as from the Union Ministry of Women and Child Development.
A number of such cases, including the one in Hyderabad, had forced the commission to intervene in the matter, it added.
According to the police, the four accused were taken to the scene of the crime, around 60 Km from Hyderabad, for a re-construction as part of the investigation.
According to the police, one of the accused signalled to the others, possibly to escape, and they tried to snatch the weapons of the police personnel when the latter fired on them and they were killed allegedly in the cross-firing.
The charred body of the woman, working as an assistant veterinarian at a state-run hospital, was found under a culvert in Shadnagar, near Hyderabad, on the morning of November 28, a day after she went missing.
The four men, all lorry workers aged between 20 and 24 years, were arrested on November 29 for allegedly raping and killing the woman by smothering her and later burning her body.