Ahmedabad: A special fast track court here Tuesday convicted 31 people and acquitted 63 in the Godhra train carnage case in which 59 people on board the Sabarmati Express were burnt to death, triggering communal frenzy in Gujarat in 2002.

The unrest, some of the worst religious violence in India since independence, was sparked after 59 Hindu pilgrims perished in a train fire at Godhra station in the western state of Gujarat.

Hindus in the state blamed the blaze on Muslim protesters at the station, and furious mobs seeking revenge rampaged through Muslim neighbourhoods in several cities during three days of bloodshed.

Special public prosecutor J.M. Panchal told reporters outside the court in Ahmedabad city: "31 people have convicted under conspiracy and murder charges, 63 others have been acquitted."

A total of 94 people, all Muslims, stood trial for causing the train blaze.

Responsibility for the fire has been the subject of fierce dispute between India's Hindu and Muslim communities, and Tuesday's convictions supported Hindu claims that it was a planned attack.

Previously one national inquiry concluded the fire was an accident, though other official investigations contradicted that finding.

"The court has accepted the conspiracy theory. It was not an accident," Panchal said, adding sentences would be handed down on Friday.

Extra police were on duty across Gujarat to prevent any outbreak of communal violence in the wake of the verdicts, which came after the trial concluded in September.

Authorities also banned television stations and newspapers from broadcasting or printing the many graphic images taken during the riots to avoid stirring up religious tensions.

Gujarat's chief minister Narendra Modi - a strident Hindu nationalist - was accused of failing to stop the riots, and even of encouraging them, with police allegedly ordered not to intervene as the killing spread.

Muslims have always denied setting the train ablaze on February 27, 2002, though an angry crowd had gathered at Godhra station to protest against the daily stream of Hindu passengers allegedly taunting Muslim porters and hawkers.

The Hindus on the train were returning from the town of Ayodhya, another flashpoint for inter-religion unrest after a mosque was razed in 1992 by Hindu zealots, leading to riots that killed thousands of people, mostly Muslims.

Some observers feared a court ruling on Ayodhya last year would revive such scenes of carnage, but there was little public unrest after judges declared that the mosque site should be divided between Hindus and Muslims.

Modi, a member of the opposition Bharatiya Janata Party (BJP), has struggled to shrug off accusations about his handling of the riots.

After the train blaze, he quoted Isaac Newton's law that "every action has an equal and opposite reaction" - words seen as a deliberate signal of support for the vengeful killers.

He has since transformed Gujarat into one of India's most successful states, attracting massive business investment.

A Supreme Court panel earlier this month criticised him over the events of 2002, saying he had been "partisan" and had sought to play down the seriousness of the violence.

It noted his 'discriminatory attitude' in visiting the scene of the train fire at Godhra, but not the riot-affected areas in Gujarat's largest city, Ahmedabad.

Modi, who is seen by many in his party as a future prime minister, denies all allegations against him over the riots.

During the slaughter in Ahmedabad and elsewhere, baying Hindu mobs surrounded and raped Muslim women, then poured kerosene down their throats and their children's throats and threw lit matches at them.

Many witness reports suggested police directed rioters to Muslim homes and also turned fleeing Muslims back towards the killers.

Previous investigations commissioned by the Gujarat government have absolved the state police and government of any collusion in the violence, which left 200,000 people homeless. Many Muslims never returned.