A British paratrooper today claimed he shot a nail bomber on Bloody Sunday.
But outside the Saville inquiry today, the man the soldier is believed to have shot denied he was carrying any device.
Peering through his rifle sights, the corporal with the machinegun platoon of the 1st Battalion of the Parachute Regiment had a clear view of a man striking a match against a wall to light a nail bomb in his right hand, the paratrooper's witness statement says.
The officer, identified only as Soldier A, said he made the split second decision to shoot, believing the target was bringing both hands together.
"There was no time to shout and ask for permission before I fired," his statement to the Bloody Sunday Inquiry, sitting in central London, says.
"The Yellow Card [the document containing the British army's rules of engagement] gave me authority to shoot nail bombers. My intention was to stop him throwing the nail bomb in our direction. I fired a shot. He was still standing. I fired another round and hit him".
This was about 15 minutes before British paratroopers entered Derry's Bogside and killed 13 Catholic men and wounded another 13 people on the civil rights march.
Soldier A opened fire on the edge of the Bogside where Damien Donaghy (15) and John Johnston (59) were shot. His statement says he had cocked his rifle earlier after hearing what he believed were two bombs go past the window of a derelict building in William Street where his platoon had positioned themselves to arrest rioters.
Mr Johnston, who is widely considered as the 14th victim of Bloody Sunday, received several injuries and died five months later of a brain tumour. Mr Donaghy, who was watching as Soldier A gave his evidence, denies he was a bomber.
"The second shot hit the guy," Soldier A continues in his inquiry statement. "His body went up and back with his hands flung up in the air. Without sounding flippant it was something like they do in the movies and is due to the force of the 7.62 round which really does send shockwaves".
It is unclear whom Soldier A shot because another paratrooper, identified as Private B, simultaneously opened fire at the man towards the corner of the building, the inquiry heard.
Photographs Soldier A has been shown since of Mr Donaghy have not triggered a memory of whether the youngster was his target that day.
In a statement issued outside the hearing, Mr Donaghy again stressed that he was not a nail bomber. He said: "Today the paratrooper who admits to firing live rounds on Bloody Sunday is giving evidence. I am the person that he is likely to have shot.
"For 31 years he and fellow members of his platoon have branded me as a nail bomber. I am not a nail bomber. Over 70 witnesses, including civilians, priests and journalists, have given evidence to the inquiry that there were no nail bombs thrown or explosions caused in William Street on Bloody Sunday".
Announcing the inquiry into the shootings in January 1998, Prime Minister Tony Blair told the House of Commons that all of those shot should be "regarded as innocent of any allegation that they were shot while handling firearms or explosives".
Thirteen civilians were shot dead by the British army on Bloody Sunday, January 30th, 1972.