After nine months of agonising wait for the victim’s family, a fast track court in New Delhi on Tuesday held all four accused guilty of a criminal conspiracy to gangrape, murder and commit unnatural sex on the 23-year-old physiotherapy student on December 16, 2012.

The quantum of sentence is likely to be decided on Wednesday.

The heinous crime against the “helpless woman” was committed by six accused, including a juvenile, on a moving bus when she, along with her boyfriend, was returning home after watching the evening show of Life of Pi at Saket PVR in South Delhi.

The accused were also found guilty of attempting to kill the boyfriend by brutally assaulting him when he tried to defend her, and of abduction, dacoity and robbery.

The victim’s dying declaration, the eyewitness account of her boyfriend and the DNA test proved crucial for the court to hold the accused guilty.

Though the case against prime accused Ram Singh was abated after he committed suicide at Tihar Jail here when the trial was in progress and the juvenile was held guilty by the Juvenile Justice Board and sent to a correction home last month, the fast track court held the two guilty of these offences.

Additional Sessions Judge Yogesh Khanna said Akshay Thakur, Vinay Sharma, Mukesh Singh and Pawan Gupta had conspired to gang-rape and murder the victim as they “deceitfully” got her and her boyfriend to board the bus, making them believe that it was a public transport vehicle, before shutting the door and not allowing any other passenger along the route to get in.

Shedding more light on the conspiracy charge, Justice Khanna said the accused put off the interior lights of the bus, pinned down the victim’s boyfriend in the middle of the vehicle, took the woman to its rear seat, pulled off her clothes and committed the crime. So the purpose of the accused was not to earn fare by allowing the victim and her boyfriend to board the bus but to defile her body and murder her.

“The act of abducting the victim by deceit, robbing, causing injuries and the act of some accused in pinning down the complainant [the boyfriend] while others took their turns in committing rape/unnatural sex and while one of them continued driving the bus and lastly throwing them out of the moving bus, sharing the booty, destroying evidence thoroughly show illegal agreement among them to commit such an illegal act and they had knowledge of the same,” the judge said.