The main accused in the fatal gang-rape of a 23-year-old student on a bus in New Delhi last December hanged himself in jail Monday while in solitary confinement, police and prison officials told AFP.

"Yes, he is dead," an official said in the control room of New Delhi's Tihar Jail when asked about Ram Singh, the man suspected of leading the gang-rape which ignited street protests and a round of soul-searching about women in India.

A senior police officer on the case, who also asked not to be named, told AFP that the 35-year-old widower had hanged himself at 5:15 am in his cell.

"The case will continue. There is no reason for the case to suffer," said the officer.

Singh, whose brother is also an accused, was being held in top security in Tihar and making regular appearances in court where he faced murder, rape and kidnapping charges among others which could have brought the death sentence.

He was the regular driver of the white private bus alleged to have been used for the December 16 crime, which was normally used to ferry school children.

Police say Singh and friends had had a meal together and had been drinking heavily before deciding to take the bus out for a night-time joyride.

The 23-year-old victim died 10 days after her ordeal which brought simmering anger about endemic sex crime in India to the boil.