A former Catholic priest has spoken of his treatment on Bloody Sunday by Soldier F, a paratrooper who the Saville Report identified as killing four people.
Professor Terry O'Keefe told BBC Radio Foyle that he was attacked by the paratrooper shortly after he was taken in a lorry to Fort George.
"We were kicked out of the lorry and we had to run through a gauntlet of eight to 10 paratroopers who were striking people as they ran," he said.
"For a couple of hours we were being looked after by Soldier F and Soldier G, quite a ferocious looking, slightly crazed looking paratrooper.
"It was then that I became aware of a lot of idle brutality, stamping on feet, kicking people in the groin, thumping people, for no apparent reason, I think just to pass the time."
Professor O'Keefe also said some of those detained had their faces pushed towards electric heaters to cause "discomfort and pain".
"A senior officer came in and pointed to me and said: 'Who is charging that man?'," he continued.
"Soldier F mumbled something and the senior officer said: 'Charge him, you saw him throwing stones'.
"I did try and tell him I was a Catholic priest and lecturer in philosophy and did not throw stones.
"At that stage I got a kick in the groin and he urged me to wear my Roman collar."
He said Solder F had appeared 'calm' throughout his detention.
"He clearly was not moved by the sort of shooting that he was responsible for or the shots that he was alleged was incoming fire."