The city was in uproar after the gang rape last Sunday of a 23-year-old physiotherapy student who, after her male companion was beaten unconscious, was grabbed on a bus by six men, gang-raped and beaten with an iron bar for more than half an hour before being thrown naked and bleeding from the moving vehicle onto the side of the road.

Sexual assaults on young women by groups of men are not uncommon in Delhi - the city carries the unhappy sobriquet of the ''rape capital of India'' - but the particular brutality of this attack has sparked widespread anger.

National Crime Records Bureau figures show a quarter of India's rapes are reported in the capital, despite Delhi representing just 1.38 per cent of the country's population.

In 2011, Delhi (572) had more reported rapes than Mumbai (221), Kolkata (46), Chennai (76), Bangalore (97) and Hyderabad (59) combined.

On Saturday, thousands of demonstrators, mostly young men and women, marched down Rajpath, Delhi's grandest boulevard, to protest against the culture of sexual violence in the city, and what they view as official apathy towards the problem.

As the marchers approached Raisina Hill, home to the Prime Minister's office and the presidential palace, they were stopped by barricades and forcefully pushed back by 1500 police officers armed with lathis - long bamboo batons - and riot shields.

All six of the alleged assailants from last Sunday's attack have been arrested, but Delhi's police are viewed by many as corrupt, lazy and incompetent, and of routinely dismissing sex assault complaints. Senior officers are regularly quoted as saying that women who are sexually assaulted have themselves to blame - for wearing jeans, for being out at night, for talking to boys, or getting into cars with them. Even senior female politicians have blamed women for attacks.

The Chief Minister of Delhi, Sheila Dikshit, said she hated the ''rape capital'' tag and supported the death penalty for rapists. But last year, after a young woman was raped and murdered on the city's outskirts, her response was ''all by herself till 3am … you should not be so adventurous''.

The investigative magazine Tehelka recently interviewed dozens of senior police in the Delhi region about the spate of rape cases in and around the capital. Their responses overwhelmingly accused women of inviting the attacks on them.

The victim of last Sunday's attack has recounted her ordeal to a magistrate from her hospital bed. She is suffering severe intestinal injuries and infection. She was described as ''fearless and bold'' by the Deputy Commissioner of Police, Chhaya Sharma.

The government said on Sunday it would amend criminal laws to include stronger punishment, and possibly the death penalty, for ''rarest of the rare cases of sexual assault''.

with Bloomberg