Passers-by left a gang-raped Indian student lying unclothed and bleeding in the street for almost an hour, a male friend who was assaulted with her has said in his first public comments.

The 23-year-old student died in hospital two weeks after she was attacked on 16 December in a private bus in New Delhi, prompting street protests over the Indian authorities' failure to stem violence against women.

The graphic account from the man in a television interview is likely to add to public anger over the death in a country where official statistics show one rape reported every 20 minutes.

The woman's friend told the Zee News television network he was beaten unconscious with a metal bar by her attackers before the pair were thrown off the bus.

They lay in the street for 45 minutes before a police van arrived and officers then spent a long time arguing about where to take them, the man said.

"We kept shouting at the police, 'please give us some clothes' but they were busy deciding which police station our case should be registered at," the man said in Hindi.

Delhi police spokesman Rajan Bhagat told Reuters GPS records show the first police van reached the scene four minutes after it was were called and took the man and the woman to hospital within 24 minutes.

Neither the woman nor her friend have been named.

Five men were charged with her gang rape and murder yesterday. A court is due to consider the charges tomorrow.