AHMEDABAD -  An Indian court on Thursday upheld appeals by 14 Hindus convicted over the massacre of 33 Muslims burnt alive during some of the worst religious unrest the country has seen since independence.

The victims had crowded into a small house seeking shelter during a wave of anti-Muslim violence in the western state of Gujarat in 2002, triggered by a train fire in which Hindu pilgrims were burnt alive.

The rioters set the house alight, killing 28 people on the spot. Another five later died of their injuries.

The court in Gujarat upheld the convictions of another 17 people sentenced to life in prison in the original 2011 trial for their role in the killings in the village of Sardarpura.

"Out of the 14 acquitted, the bench granted benefit of doubt to 11, while it said it did not find evidence against three others," said defence lawyer NL Jain after the hearing.

All 31 men were originally handed life sentences for murder, arson and other charges in the Sardarpura case.

The attackers first surrounded the village, blocking off any escape, and then moved in.

Gujarat's Hindu nationalist government was accused of tacitly supporting the attacks, and survivors of the Sardarpura massacre said it could have been avoided if the police had arrived on time.

"We were shouting, pleading and begging. But no one came to our help, not even the police," Bifu Mia told AFP at the time.

More than 100 people have been convicted over the riots, which left more than 1,000 people dead in some of India's worst inter-faith violence since independence in 1947.

Muslims were blamed for the train fire and Hindu mobs hungry for revenge rampaged through Muslim neighbourhoods in towns and villages across Gujarat during a week of bloodshed.

Indian Prime Minister Narendra Modi, who was the state's chief minister at the time, was accused of turning a blind eye to the violence.

He was cleared of any wrongdoing in 2012 by a Supreme Court-ordered investigation but has been dogged by the accusations.

Witnesses said mobs surrounded and raped Muslim women, poured kerosene down their throats and on their children and threw lit matches at them.

Earlier this year a court jailed 11 Hindus for life over the massacre of dozens of Muslims hacked and burnt to death in a residential complex in the city of Ahmedabad in Gujarat.

The massacre at the Gulbarg Society housing complex was one of the single worst losses of life in the week-long violence.