The state government in Uttar Pradesh, where the killings took place, has been accused of tolerating lawlessness and criticised over insensitive comments made by its political leaders.
But the head of police for the region has claimed the atrocity may not be as it first appeared. Only one of the girls had been raped and the five men sought for their murder may be innocent, he said.
The victims had in fact been strangled before their bodies were strung up on the tree, he added. Anand Lal Bannerjee said the girls' relations and witnesses in the case would now be made to undergo "narco-analysis" - whereby they will be questioned while under the influence of "truth drugs". Their telephone records will also be examined.
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• Gang rape reflects India's immense cultural divide
Ranjana Kumari, a leading campaigner for women's safety, said the comments by the state police chief could not be trusted and may be aimed at easing pressure on the Uttar Pradesh government. "The police are making contradictory statements and creating further confusion," she said.
On Saturday, Ramsevak Paikra, the home minister of central Chhattisgarh state, said rapes happen "accidentally" when he was asked for his thoughts on the killings.
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