A trial court had on Friday held the policemen guilty of a fake encounter.
On July 12, 1991, the policemen stopped a luxury bus filled with Sikh pilgrims in Uttar Pradesh's Pilibhit district and forced 10 passengers to get off.
A charge-sheet said they were divided into groups, taken to different areas in a jungle and killed in "cold blood."
The policemen claimed the next day that 10 Khalistani terrorists had been killed. They claimed that some of the Sikhs in the bus had criminal cases and were armed.
The Central Bureau of Investigation (CBI) investigated the case on the orders of the Supreme Court and said that the motive behind the killings was to earn awards and recognition for killing terrorists.
Fifty-seven policemen were charged in the case, but 10 have died since.