Five men accused of the brutal gang rape and murder of a 23-year-old Indian woman have been formally charged in a New Delhi court.
Police have filed a number of charges against the men, including rape, murder, kidnapping and destruction of evidence.
They could face the death penalty if convicted.
A sixth person alleged to have taken part in the rape will not be charged until police can establish whether he is over the age of 18.
Armed police maintained tight security at the Saket district court before the hearings began, although the men did not appear.
New Delhi police have compiled a 1,000-page evidence brief about the attack that took place on a bus in South Delhi.
It is alleged all six suspects raped and bashed the woman, who died in hospital in Singapore after a 13-day struggle to survive injuries so grievous that part of her intestines had to be removed.
Who are the suspects?
Ram Singh, 35
The alleged ringleader, who lives in a Delhi slum
The regular driver of the private bus allegedly used in the crime
Was allegedly drunk when he decided to take the bus out for a night-time joyride
Mukesh Singh, 26
The brother of Ram Singh
Worked as an occasional driver and cleaner of the bus
Accused of taking part in the rape as well as hitting the woman and her boyfriend with an iron rod
Vinay Sharma, 20
Worked as a gym assistant and fitness trainer
Has allegedly confessed to beating up the boyfriend
Reportedly denies raping the girl
Akshay Thakur, 28
Worked as a helper on the bus
Also accused of trying to destroy evidence by helping to wash the bus after the incident
Pawan Gupta, 19
Worked as a fruitseller
Reported by The Hindu to have said "I have done a horrible thing" during an earlier court appearance
Suspect no. 6
A a minor whose name cannot be given for legal reasons
Thought to be 17, police are checking his age with a bone test
Police allege the men drove the bus around for almost an hour, assaulting the woman before throwing her from the bus and trying to run her over.
Authorities have obtained a statement from the victim and an account from her boyfriend, who was with her at the time.
He was beaten during his attempts to save the medical student.
Lawyers at the district court in New Delhi have decided they will not defend the suspects, meaning that the government will have to appoint advocates for them.
Outside the court, lawyers in black robes protested, demanding the judicial system act faster against rape.
"We want the laws to be amended in such a stringent way that before a person even thinks of touching a girl, he should feel chills down his spine," protesting lawyer Suman Lata Katiyal said.
Large demonstrations are continuing in New Delhi with people calling for more to be done to protect women.
These two women say they are happy the men have been charged, but that police should be focused on prevention.
"We are saying that why should such an incident happen?"one woman said.
"Why should the police be filing such a case? Because their role should be to stop such things from happening rather than filing charge sheets."
The other said: "A strict punishment should be given to them. A very strict punishment that the all men of India should be aware that they are not going to treat the women like the way they treated her."
Altamas Kabir, the chief justice of India, has cautioned against letting public anger overwhelm the due process of the law.
"Let us not get carried away. A swift trial should not be at the cost of a fair trial," he was quoted as saying in the local media.
The government has faced a wave of public anger over the attack and one minister suggesting new anti-rape legislation should be named after the victim.
This sparked a controversy as her name has not been disclosed, in line with legal protections given to the victims of sex crime and their families, who face social stigma.
Prosecutors are confident the trial will be finished in six weeks.
The case began as the father of the physiotherapy student, whose gang-rape and death sparked public outrage against the government, has demanded those responsible be hanged and called for new legislation on sex crimes to be named in honour of his daughter.
"The whole country is demanding that these monsters be hanged. I am with them," the father told reporters in his home village of Mandwara Kalan.
The woman's father told reporters he supported a proposal to name revised legislation in his daughter's honour.
"She is the one who has been sacrificed," he said.
Her father said he was demanding a change in the law to allow for the execution of juveniles.
The studious, ambitious young woman was determined to improve life in her village, her father said.
"She said 'papa, the place of your birth is very backward, if I become a doctor I will first improve life in the village,'" he said.
"I remember asking her once, who are your friends, and she replied, dad, it's only my books I'm friends with. She always wanted to be a doctor and that's why we moved from this rural place to Delhi... to give our children a better future."
The government has set up two panels headed by retired judges to recommend measures to ensure women's safety. One of the panels, due to make recommendations later this month, has received some 17,000 suggestions from the public, media reported.
The district court where the charges are due to be heard is expected to assign a defence lawyer for the five men after the bar association said none of its members were willing to represent them.