It came as the top official in the north Indian state of Uttar Pradesh, where the incident took place, mocked journalists for asking about the attack.
"Aren't you safe? You're not facing any danger, are you?" Chief minister Akhilesh Yadav said in Lucknow, the state capital. "Then why are you worried? What's it to you?"
The gang rape, with video of the cousins' bodies hanging from a mango tree, was the top story on India's news stations. But Uttar Pradesh has seen the mother of a rape victim attacked and a 17-year-old girl gang-raped by four men.
Uttar Pradesh is India's most populous state, with nearly 200 million people.
Statistics say about 25,000 rapes are committed every year in India, a nation of 1.2 billion people. But activists say that number is very low, since women are often pressed to stay quiet about sexual assaults.
Indian police and politicians have faced growing public anger since the December 2013 gang-rape and murder of a woman on a New Delhi bus, an attack that sparked national outrage.
The state's former chief minister has lashed out at the ruling government. "There is no law and order in the state," said Mayawati. "It is the law of the jungle."
Hours later, the chief minister ordered that suspects in the attack be tried in special "fast track" courts, to get around India's notoriously slow judicial system.
The girls, who were 14 and 15, were raped in the village of Katra, about 180 miles from Lucknow.
Police say they disappeared on Tuesday night after going into fields at their home to relieve themselves, since their house has no toilet. The father of one girl went to police that night to report them missing, but said they refused to help.
When the bodies were found the next day, villagers protested the police inaction by refusing to allow the bodies to be cut from the tree.
Villagers allowed authorities to take down the bodies after the first arrests were made on Wednesday. Police arrested two police officers, two men from the village and were searching for three more suspects.
The fired policemen and the men accused in the attack are Yadavs, a community that dominates that part of the region.
Top state official Anil Kumar Gupta said the two policemen had been charged with criminal conspiracy.
The chief minister's mocking comments to reporters are not a surprise to many in India. Last month, Yadav's father - head of the state's ruling party - told an election rally that the party opposed a law calling for gang rapists to be executed. "Boys will be boys," Mulayam Singh Yadav said. "They make mistakes."
Kavita Krishnan, a women's rights activist, said such comments make clear to police that rape isn't taken seriously by officials.
There have been a string of high-profile attacks in the past few days in Uttar Pradesh.
On Thursday, police arrested three men for brutally attacking the mother of a rape victim after she refused to withdraw her complaint.
The attack, in the town of Etawah, followed the May 11 rape of the woman's teenage daughter. A local man was arrested after the mother filed a complaint with authorities. Five men, including the father, a brother and a cousin of the man accused in the rape, beat the victim's on Monday, demanding she drop the accusation. The mother is in critical condition in a hospital.
Police arrested three men on Thursday for the attack and were looking for two others.
On Wednesday, a 17-year-old was attacked in a field and raped by four men in southwestern Uttar Pradesh. A man has been arrested.
l Malaysian police have detained 13 men and are looking for more following allegations that a 15-year-old girl was raped by 38 men in an abandoned hut.
Local media reported that the assault took place in the northern state of Kelantan on May 20 when the girl was lured to an empty hut.