Two eyewitnesses in the north-east Indian state of Manipur say that a senior rebel leader, Sanjib Singh, who was arrested while travelling in their car, was later shot dead by the police.
The allegation was made at a news conference organised by Manipur's leading human rights group, the Committee on Human Rights (COHR).
The eyewitnesses, Oinam Dilip and Inaoba Singh, said they had given a young man a lift on their car on the 6 July in the state capital, Imphal.
But they said their car was stopped at a check-post, where policemen on duty identified the young man as Sanjib Singh and dragged him away.
Oinam Dilip and Inaoba Singh , who were also taken to the police station, say they heard gunshots at a distance and were later told that the rebel leader had fled.
But the next day, Sanjib Singh's body was fished out of a nearby river.
Police officials admit they had arrested Sanjib Singh but say that he was shot when he tried to flee.
The Committee on Human Rights says this is the first time that direct eye witnesses have agreed to testify in an alleged fake encounter in Manipur.
From the newsroom of the BBC World Service