Could the man who murdered a Christian missionary and his sons walk free in India?

Warning: This article contains details of violent death that some readers may find distressing

One of India's most shocking incidents of anti-Christian violence is back in the news more than a quarter of a century after it drew condemnation from around the world.

On Wednesday, the Supreme Court is due to take a call on a petition seeking release from prison by a man, who is convicted of killing Australian Christian missionary Graham Staines and his two young sons in 1999.

Dara Singh - whose real name is Rabindra Kumar Pal - has been in jail since his arrest in 2000, serving a life sentence for burning alive the Australian missionary and his six and 10-year-old sons in a village in the eastern state of Odisha (formerly Orissa).

Staines had spent 30 years working with leprosy patients, but Singh and his associates from Hindu hardline groups had accused him of forcibly converting poor Hindus from disadvantaged castes and tribals to Christianity.

The viciousness of the crime sent shockwaves through India's minority Christian community and caused global outrage. Now reports that Singh may be set free have brought alive memories of the heinous crime.

Staines lived in Baripada in Mayurbhanj district, where he worked among the local tribal community.

On the night of their murder on 22 January 1999, Staines and his sons had attended a Christian gathering in Manoharpur, a remote village in the neighbouring district of Keonjhar. They were sleeping in their jeep when a mob of 60 to 70 people led by Singh surrounded their vehicle, set fire to it and prevented them from escaping.