The police told Metropolitan Magistrate Namrita Aggarwal that the other three arrested culprits, Ram Singh's brother Mukesh, Vinay Sharma, an assistant gym instructor, and Pawan Gupta, a fruit seller, will be produced in court tomorrow.
Doctors at the Safdarjung Hospital, where the victim is being treated, said she had responded to the doctor's call and raised her hands in the morning and even read something which the doctors wrote on a paper.
Delhi Police Commissioner Neeraj Kumar told reporters that the girl was in a "serious condition" but was doing
better than yesterday.
Dr B D Athani, Medical Superintendent of Safdarjung Hospital, said, "Her condition is better than yesterday. Her conscious level is much better than yesterday's. She underwent a surgery on Sunday."
The victim's male friend, an engineer who objected the men making lewd remarks at the victim, was also beaten up during the incident, which led to widespread outrage in Parliament and outside and demand for death penalty for rapists.
Investigators said that they will seek a fast-track trial for speedy justice in the case as well as write a proposal to Union Home Ministry seeking laws for invoking death penalty for rapists.
The Police Commissioner said the driver of the chartered bus, which was not legally permitted to run on normal routes, his brother and two more people had been arrested, while a massive manhunt has been launched to nab the remaining two accused. He said the accused were on a "joyride".
"Disturbed" over the gang-rape, the Delhi High Court assured women lawyers that it was looking into the "brazen" incident following a plea for a court-monitored probe.
Meanwhile, Delhi Chief Minister Sheila Dikshit asked Chief Justice of Delhi High Court Justice Darmar Murugesan to immediately make functional five Special Fast Track Courts to try cases of assult on women, as approved by the Delhi government.
The Chief Minister, in a letter to the CJ, urged him to take "urgent" action in making the fast track courts functional.
While Ram Singh, Sharma and Gupta were arrested from the capital, Mukesh was nabbed from Rajasthan and had been brought to the capital, the Police Commissioner said, terming the incident as "most reprehensible".
The girl, who had come to Delhi from Dehradun for her internship, and her friend had boarded the bus at Munirka to go to Dwarka.
While Neeraj Kumar said two men were still absconding in connection with the incident, police later in court said three persons were absconding and they need to send teams to Bihar, Uttar Pradesh and Rajasthan to nab them.
"Ram Singh, who was not driving the vehicle that night, shouted that the bus was going to Dwarka and asked the couple to get into it. Once the bus started moving, they started misbehaving with the girl. Her male friend who protested and tried to save the girl was severely beaten up. The girl also tried hard to protect him," Kumar said.
But she was raped allegedly by Singh and other occupants of the vehicle which was being driven by Mukesh at the time of the incident. The duo were then brutally assaulted and dumped near Mahipalpur flyover, he said.
Kumar said the Delhi Police will seek a fast-track trial in this case on a day-to-day basis so that the accused given justice as soon as possible.
To a question, Kumar said the maximum punishment for this crime was life sentence, but as far as the demands for death sentence for such crimes are concerned, the Delhi Police will send a proposal in this regard to the government.
The city police chief said the bus, which was primarily a school bus, was being used for commercial purposes illegally by the driver.
On the sequence of events, Kumar said the men had allegedly looted a carpenter Ramadhar, whom they offered transport from R K Puram to IIT Gate, at around 8:30 pm, just before they reached Munirka from where they picked up the victim and her friend.
"The men in the bus started asking the them why they were travelling in the night and what they were up to. The male friend told them why should they be bothered. Then they picked up a fight and the boy was hit on his head. The girl also fought with them to save her friend but was hit.
"Then they were enraged and dragged the girl to backseat where they sexually assaulted her," Kumar said.
After assaulting them and dumping them, Ram Singh took to the wheels and then dropped the other five at their houses before parking the vehicle at his owner's place in Noida where he washed the bus in a bid to destroy evidence.
The next day, Monday, he drove back the bus to R K Puram but landed in the police net as investigators were waiting for him after tracking the bus. "The bus was cleaned. But we have got enough forensic evidence like nail scratchings, DNA, hair and lot of other things," Kumar said.
On Monday, almost all the accused went ahead with their daily job, he said
Tracking the bus helped investigators to crack the case soon, a senior police official said, adding the male friend gave them proper description about the bus and the seating arrangement.
"He told us that the colour of the vehicle was white and the word 'Yadav' was written on it. It was like a luxury bus. With the help of Transport Department records, we zeroed in on around 370 buses. Then we zeroed in on owners with surname Yadav and we found two.
"We went to first person who denied any involvement. Then we went to Dinesh Yadav. He told us that it could be his driver," he said.
The bus was spotted in Sector 3 of R K Puram yesterday afternoon and was impounded immediately. "The driver cleaned the bus but forensic examination revealed this was the bus in which the incident took place. The duo were dumped from the front gate of the bus," Kumar said.
To a question, Kumar said while the boy was hit by an iron rod, the girl was punched badly in her stomach.
The incident triggered outrage with students of Jawaharlal Nehru University staging a demonstration outside Vasant Kunj Police Station and blocking traffic.