Six charged with murder after rape victim dies

"Your voice has been heard," Gandhi said. "It deepens our determination to battle the pervasive and the shameful social attitudes that allow men to rape and molest women with such impunity."

Delhi's chief minister, Sheila Dikshit, said the woman's death was a "shameful moment for me not just as a chief minister but also as a citizen of this country".

The woman, who has not been identified, and a male friend were returning home from the cinema by bus on the evening of December 16th when, media reports say, six men on the bus beat them with metal rods and repeatedly raped the woman. Both were thrown from the bus. The male friend survived.

The attack has put gender issues centre stage in Indian politics arguably for the first time. Issues such as rape, dowry-related deaths and female infanticide have rarely entered mainstream political discourse.

Analysts say the death of the woman dubbed "Amanat", an Urdu word meaning "treasure," by some media could change that, although it is too early to say whether the protesters calling for government action to better safeguard women can sustain their momentum through to national elections due in 2014.

The public outcry over the attack caught the government off-guard. It took a week for Singh to make a public statement on the attack, infuriating many protesters who saw it as a sign of a government insensitive to the plight of women.

The prime minister has struggled to channel the popular outrage in his public statements and convince critics that his eight-year-old government will now take concrete steps to improve the safety of women.

"The Congress mangers were ham-handed in their handling of the situation that arose after the brutal assault on the girl. The crowd management was poor," a lawmaker from Singh's ruling Congress party said on condition of anonymity.

Protesters fought pitched battles with police around the capital last weekend. Police used batons, water cannon and teargas to quell the protests.

Commentators and sociologists say the rape has tapped into a deep well of frustration many Indians feel over what they see as weak governance and poor leadership on social issues.

New Delhi has the highest number of sex crimes among India's major cities, with a rape reported on average every 18 hours, according to police figures. Government data show the number of reported rape cases in the country rose by nearly 17 per cent between 2007 and 2011.

Indian media had accused the government of sending the woman to Singapore to minimise any backlash in the event of her death but Raghavan said it had been a medical decision intended to ensure she got the best treatment.

Home minister Sushilkumar Shinde told Times Now television the government was committed to ensuring "the severest possible punishment to all the accused at the earliest".

"It will not go in vain. We will give maximum punishment to the culprits. Not only to this, but in future also. This one incident has given a greater lesson" Mr Shinde said.

He said earlier the government was considering hanging for rape in rare cases. Murder already carries the death penalty.