Two police officers in India have been sacked for refusing to help search for two missing girls who were later found gang-raped and hanged, authorities say.
Three suspected attackers have been arrested, along with two policemen accused of dereliction of duty and criminal conspiracy.
The government has pledged to set up a fast-track court to prosecute the attack this week in Uttar Pradesh.
Alleged police inaction sparked outrage in the teenagers' village.
The father of one victim told the BBC 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".
Meanwhile, reports have emerged that two more gang rapes of minors occurred in the state this week.
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
'You are safe'
The chief minister of Uttar Pradesh reacted angrily when asked about the rising number of rape cases at a news briefing.
"You are safe, why are you bothered?" Akhilesh Yadav told a journalist.
"No other state has the kind of police control room we have here. If there is any incident, we will take action."
Senior police official Atul Saxena earlier announced there would be a "thorough investigation" into the allegations of caste discrimination by police.
Divisions between India's castes run deep, and violence is often used by upper castes to instil fear in lower castes, correspondents say.
Although both the victim and the accused in the latest case belonged to a group known as "Other Backward Classes", the victims were lower in that hierarchy.
The girls, two cousins aged 14 and 16, went missing in Badaun district on Tuesday night. They had apparently gone out to relieve themselves as they had no toilet at home.
Their bodies were discovered the following day. A post-mortem examination confirmed multiple sexual assaults and death due to hanging.
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 use the toilet, particularly at night.
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.
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