HARJIT SINGH, 22, a former employee of the Punjab State Electricity Board and father of two small children, 'disappeared' last April. There is nothing very unusual about that, for hundreds of young Sikhs have 'disappeared' in the Punjab over the past few years as armed Sikh opposition groups, demanding an independent Sikh state, have been locked in conflict with police and security forces.

What makes it different is that his parents have put together an exceptional amount of information about their missing son and that Sikh human rights groups have decided to make his disappearance a test case with the Indian government and judiciary. A petition for habeas corpus for Mr Singh is being heard today in the High Court in Haryana and John Major, the Prime Minister, has been presented with all relevant documents by the British Sikh community as he leaves for a visit to India.

A 'disappearance' in Punjab has come to mean almost certain death. But from recent information it seems possible that the young man has escaped the extrajudicial execution that frequently follows such arrests, and may still be alive somewhere in custody. Since death could follow at any moment, Mr Singh's case has been labelled an 'urgent action' by Amnesty International.

Harjit Singh was travelling on a bus on 24 April, returning from an interview with his former employers with whom he was again trying to find work, when the bus was stopped by police and he was arrested. His family know that he was detained first at various police stations. They know the names of the police who arrested him, and those of the officers in whose custody he was. They know that he was tortured, so badly that at one point he could not walk. His legs may have been broken.

They know, too, that he was then taken to the Mal Mandi interrogation centre in Amritsar City. His father, alerted by witnesses, arrived at the centre. He was told his son was dead, shot by a group of armed terrorists who attacked a police party apparently taking him to recover a cache of hidden arms. Police then produced ashes said to be those of Harjit Singh. Blaming deaths on armed 'encounters' has become a routine police tactic.

However, five months later, Mr Singh was suddenly spotted in the Beas area, near Amritsar, with a police escort. The High Court agreed to appoint a warrant officer to investigate.

When he reached the interrogation centre, the young man was spirited away, but not before he was clearly seen at a first floor window, apparently naked and chained to a wall. Other young men were with him, also chained. By the time the warrant officer was allowed to inspect the building they had all vanished.

There is no evidence to link Mr Singh to any of the Sikh opposition groups, but mere suspicion of being sympathetic to their aims has become enough for young men in Punjab to be seized by the police. What Sikh groups now hope is that international publicity may serve to deter police and army from engaging in the practice of 'disappearing' people.