Three of the suspects in the brutal rape and death of a young woman on a New Delhi bus will plead not guilty, Manohar Lal Sharma, their lawyer, has said.

Five men have been charged with attacking the 23-year-old woman and her male companion on a bus as it was driven through the streets of India's capital.

In the Indian capital on Thursday the men appeared in court, which ended quickly after it turned out some of the official court paperwork listing the charges was illegible.

India's legal system is painfully slow, corrupt and inefficient, with many cases lasting years, even decades

The hearing, which was adjourned until Monday, had been expected to result in the case being sent to a special "fast-track" court but no decision was made.

"They are innocent," said Sharma of his three clients on Thursday.

He said he took the case in part to confront the police over "how manipulated evidence is placed for fixing the innocent people".

The woman was raped and assaulted with a metal bar on December 16 and later died of her injuries.

Rape victims are not identified in India, even if they die, and rape trials are closed to the media.

Large protests

Sharma said he represents bus driver Ram Singh, Singh's brother Mukesh, and another man, Akshay Thakur.

VK Anand, another lawyer, said he also represents the two Singh brothers. It is not yet clear if the other defendants have lawyers.

Indian officials have come under immense public pressure over the attack - accused of doing little to protect the country's women - and are eager to make sure the high-profile case moves quickly.

Large protests have taken place across India since the attack, with many women telling stories of abuse and of a police and judicial system that does little to stop it.

Authorities have charged the men with murder, rape and other crimes that could bring the death penalty.

A sixth suspect, who is 17 years old, is expected to be tried in a juvenile court.

Source: Agencies