There is outrage over police inaction in a village in the Indian state of Uttar Pradesh where two teenage girls were gang-raped and hanged from a tree.
The father of one victim says he was ridiculed by police when he sought help in finding his missing daughter.
He said that when policemen found out he was from a lower caste, they "refused to look for my girl".
At least three men, including one policeman, have been arrested in connection with the incident.
Relatives have complained that police refused to help find the missing girls, aged 14 and 16, who were cousins from a low caste.
"When I went to the police station, the first thing I was asked was my caste. When I told them what my caste was, they started abusing me," the father of one of the girls told the BBC.
Divisions between India's castes run deep. Violence is often used by upper castes to instil fear in lower castes.
Although both the victim and the accused belonged to a caste grouping known as 'Other Backward Classes', the victims were lower in that hierarchy.
The victims had apparently gone out to relieve themselves as they had no toilet at home.
Campaigners have highlighted the lack of sanitation in rural areas as being a risk to women's security as well as their health, as they are often attacked when having to go out to go the toilet, particularly at night.
Further suspects hunted
Police said two men had been arrested for the rape and murder of the girls.
A constable was also detained for conspiring with the suspects and for dereliction of duty, authorities said, adding they were looking for one more suspect and one constable.
Indian media reacts to hangings
The incident has received top coverage on India's main TV channels such as NDTV, Times Now and CNN-IBN.
"Uttar Pradesh Rape shockers", reads a ticker on NDTV, which accuses the local police of being "complicit" with the attackers and quotes relatives of the two girls saying they have "no faith" they'll receive justice.
"Lawless in Uttar Pradesh" reads a top headline on CNN-IBN, which has started its own campaign using the hashtag #StopThisShame.
"UP: 3 Rapes in 48Hrs" is the lead on the Times Now channel, which reports the growing number of rape incidents in the state of Uttar Pradesh.
"Outrage" is the word used on the front pages of several leading English-language newspapers, including The Hindu and The Indian Express.
In an editorial, The Times of India lays the blame on the government of Uttar Pradesh Chief Minister Akhilesh Singh, saying the hangings "exposes the state's slide into medieval lawlessness".
Source: BBC Monitoring
Senior police official Atul Saxena said there would be a "thorough investigation" into the allegations of caste discrimination by police.
People in Katra Shahadatganj, a town in Badaun district where the incident took place, say caste "plays an important role in social affairs" in the community.
One resident, named only as Teerath, said: "If media hadn't come here the police wouldn't have done anything."
Rape cases that have shocked India
- 23 January 2014: Thirteen men held in West Bengal in connection with the gang rape of a woman, allegedly on orders of village elders who objected to her relationship with a man
- 4 April 2014: A court sentences three men to hang for raping a 23-year-old photojournalist in Mumbai last year
- 15 January 2014: A Danish woman is allegedly gang raped after losing her way near her hotel in Delhi
- 17 September 2013 : Five youths held in Assam for allegedly gang-raping a 10-year-old girl
- 4 June 2013: A 30-year-old American woman gang-raped in Himachal Pradesh
- 30 April 2013: A five-year-old girl dies two weeks after being raped in Madhya Pradesh
- 16 December 2012: Student gang raped on Delhi bus, sparking nationwide protests and outrage
A neighbour of one of the victims said the police "discriminated" against people from the lower castes in the town.
"Even though the police has suspended some constables, the ones who replace them would not be any better," he said.
But Mr Saxena denied that caste biases played any part in "influencing police behaviour" in the state.
"The police follows its rule book and considers all criminals equal before the law. There might be one or two cases like this one and we will make sure that the culprit doesn't go scot-free," he said.
Scrutiny of sexual violence in India has grown since the 2012 gang rape and murder of a student on a Delhi bus.
The government tightened laws on sexual violence last year after widespread protests following the attack.
Fast-track courts were brought to the fore to deal with rape and the death penalty was also brought in for the most extreme cases.
Some women's groups argue that the low conviction rate for rape should be challenged with more effective policing rather than stiffer sentences.