NEW DELHI: Two of the five men accused of gang-raping and murdering a 23-year-old woman in a moving bus in New Delhi last month will plead not guilty to all charges, a lawyer said on Tuesday.

“They will plead not guilty to all charges,” M.L. Sharma, who says he represents Mukesh Singh and Akshay Thakur, told AFP.

“Nothing has been proven yet.” Mukesh Singh, who is the brother of the alleged bus driver Ram Singh, and labourer Thakur are two of the five charged with rape and murder over the December 16 attack on the young student, which has fuelled protest demonstrations across India.

A sixth accused, who is 17, is to be tried in a separate court for juveniles.

Officials at Tihar jail, the maximum security prison where the accused are held, confirmed that Sharma had met the two defendants Tuesday.

Prosecutors have said they have evidence of bloodstains linking the men to the attack. But the advocate said he would challenge the police over their handling of evidence, while refusing to give details.

The next hearing, to be held behind closed doors, has been scheduled for Thursday when a magistrate is expected to transfer the case for trial in a special fast-track court.

It is not yet clear who will represent the three other defendants, all residents of New Delhi slums aged from 19 to 35.

A legal officer working at Delhi's Juvenile Justice Board, who declined to give his name, told AFP that the case of the sixth suspect would be heard on 15 January, when his age would be clarified.

“The age of the accused is not in proper order so the court asked the principal of (the) teenage accused's school to come along with age-related documents of the minor,” he said.

The brutal attack on a medical student and her boyfriend has stirred nationwide anger in India, with politicians and the victim's family calling for the death penalty for the culprits.

The pair had been to watch a film when they were lured onto a bus. The gang are accused of repeatedly raping and violating the woman with an iron bar, causing horrific internal injuries.

Although gang-rapes are commonplace in India, the case has touched a nerve, leading to three weeks of sweeping introspection on the country's attitudes to women, its often insensitive police force and dysfunctional justice system.

In a series of protests across Indian cities, demonstrators condemned the recent surge in violence against women and the apparent lack of political will to address the country's growing rape crisis.