The shot which killed teenager Jack Duddy on Bloody Sunday may have been a ricochet, a witness has told the Saville inquiry into the shootings.
James Deeney has claimed a soldier aimed his rifle towards him in the car park of Rossville Flats, but then hesitated and fired a shot into the ground, sending the round glancing past him.
When he looked round he saw a young man lying on the ground.
He said: "I assumed that the man had been hit by the same bullet although I cannot be sure as I had not seen the man fall."
Until recently he had always assumed the casualty was Mr Duddy, 17, but he added: "I can't be sure of this."
Mr Deeney, who was then 21, said that moments earlier, as he ran down Chamberlain Street towards the car park, he heard what might have been gunfire.
He then saw a soldier struggling with a man and strike him over the head with his rifle or rubber bullet gun, breaking the weapon, he said.
He also described gunfire striking the masonry above the heads of civilians seeking shelter in the Rossville Flats, the dust blinding another man, Pius McCarron.
He subsequently saw another body - possibly that of Barney McGuigan, 41 - at the other side of the flats, Mr Deeney said, adding: "There was a state of shock and general sense of horror amongst the crowd."