Six men were arrested on Thursday in connection with the alleged rape and murder of two teenage Dalit sisters in Uttar Pradesh's Lakhimpur Kheri, police said.
The girls, aged 15 and 17, were found hanging from a tree in a sugarcane field about a kilometre from their home in Nighasan police station area on Wednesday.
Police sources said the post-mortem report stated that the girls were raped while strangulation was confirmed as the cause of death.
According to preliminary investigation, the two sisters left their home on Wednesday afternoon with two of the accused, Junaid and Sohail, Lakhimpur Kheri Superintendent of Police (SP) Sanjiv Suman told reporters.
"Junaid and Sohail have confessed to strangulating the girls after raping them," Suman added.
The SP also said Junaid and Sohail were allegedly in a relationship with the two sisters.
"We have arrested Junaid, Sohail, Hafizur Rehman, Karimuddin, Arif and Chottu in an overnight operation," said Suman.
Junaid was arrested following an encounter around 8.30 am, the police said. The motorcycle used in the crime was also recovered. The police have also seized a country-made pistol and ammunition from him.
Additional Director General of Police (Law and Order) Prashant Kumar said Junaid was injured in the encounter.
"The bodies have been handed over to the girls' family, who will conduct their last rites," Kumar said.
SP Suman said the clothes of the other accused have also been sent for examination as part of a detailed probe.
A case has been registered against them under sections 302 (murder), 323 (voluntarily causing hurt), 452 (house-trespass after preparation for hurt, assault or wrongful restraint), 376 (rape) of the Indian Penal Code and the Protection of Children from Sexual Offences (POCSO) Act.
Suman also dismissed claims that police used force to send the bodies for post-mortem.
The post-mortem had been conducted with the family's consent and in their presence, he said. Videography of the post-mortem examination was also done, the SP added.
The victims' mother lodged a complaint at Nighasan Kotwali police station late on Wednesday night, alleging that her daughters were raped and murdered.
She alleged that three motorcycle-borne unidentified youths, along with her neighbour Chhotu, stormed her hutment and abducted her daughters.
When she resisted, one of them kicked her and took the girls on a motorcycle towards the fields outside the village, the victims' mother alleged.
The family later found the girls' bodies hanging from a tree in a field a few hundred metres from their village, she said.
After the incident came to light, the villagers staged a demonstration at Nighasan Cross.
The police took the bodies into custody and sent them to the district headquarters in an ambulance shortly after, while SP Suman and Assistant Superintendent of Police (APS) Arun Kumar Singh spoke to the villagers to assuage them.
A large number of police personnel were deployed to ensure law and order in the village. Kumar said senior officials from Lucknow were also sent to the spot.
The incident has triggered angry reactions from opposition parties that attacked the state's BJP government.
Bahujan Samaj Party chief Mayawati said the incident had sparked discussions everywhere. "Criminals in UP are fearless because the priorities of the government are wrong," she said in a tweet in Hindi.
"This incident exposes the claims of the government in the matter of law and order. The criminals are moving without any fear since there has been a cover-up ('leepa potee') in most of the criminal cases including the one in Hathras. The government should make necessary reforms in its policy, working and priorities," she said in another tweet.
On the other hand, the state's two deputy chief ministers -- Keshav Prasad Maurya and Brajesh Pathak -- said the government was with the victims' family and assured action against the accused.
In a tweet in Hindi, Maurya said, "Strictest action will be taken against the criminals who had raped and murdered daughters in Lakhimpur Kheri. An issueless opposition should not do politics in such matters!. The punishment given to the accused will set an example."
Pathak tweeted, "The state government stands with the family members of the victims. The government takes such an action that the future generations of these accused will shiver."
Wednesday's incident has also drawn parallels to the Buduan gang-rape of 2014.
In Budaun, two Dalit cousins, aged 14 and 15, were allegedly gang-raped and murderd and their bodies found hanging from a mango tree in Katra village.
In another incident, a 19-year-old Dalit woman was raped allegedly by four upper-caste men in Hathras on September 14 last year.
She died on September 29 at Delhi's Safdarjung Hospital.
The victim was cremated in the dead of the night near her home on September 30.
Her family members had alleged that they were forced by the local police to hurriedly conduct her last rites.
Local police officers, however, said the cremation was carried out "according to the wishes of the family".
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