A court in Delhi has heard the first descriptions of the gang rape that left a young woman so severely injured she died.
The victim's companion, who was with her when the attack took place, was the first witness to speak, India's television reported.
The 28-year-old software engineer arrived in a wheelchair, unable to walk after he was beaten with an iron rod – allegedly by the same men who assaulted his girlfriend.
His testimony took place behind closed doors, but his father told Agence France-Presse that his son had positively identified the bus on which he says the attack took place.
"My son will go to any lengths to ensure that the guilty are punished," his father said.
Five men are on trial for the murder, rape and robbery of the 23-year-old victim, who died in hospital two weeks after the Dec. 16 attack. They face the death penalty if found guilty.
A sixth suspect will be tried separately in a juvenile court, where the maximum sentence is three years in a reform facility.
According to the BBC, the defense will cross-examine the victim's boyfriend on Wednesday. Then a number of other witnesses will be called, including police officers, forensics experts and doctors.
The court will even hear from the victim herself, who recorded her testimony before she died.
Based on her statements and that of her compaion, forensic evidence and items of the victim's property found in the suspects' possession, Reuters reports, the prosecution says it has a strong case.
The five suspects have pleaded not guilty. Their lawyers claim that evidence against them was fabricated in order to obtain quick convictions in the high-profile case.