War veteran Ben Roberts-Smith threatened to choke a man to death with his bare hands in Afghanistan, and also punched and kneed an unarmed frightened prisoner, an SAS witness has told the Federal Court.

The still-serving soldier codenamed Person Seven said on Wednesday that he was searching a compound in the Deh Rafshan area in 2010 when he and another soldier located a man sitting cross-legged on carpet.

The unthreatening individual rolled over into a foetal position making a “whimpering type sound” and in ‘”serious fear” tensed up so tightly the soldiers were unable to move him, he said.

Person Seven turned to his comrade and said “this bloke is s***ing himself” and decided to give him a moment to settle down.

‘Three to four quick punches’

At that point Mr Roberts-Smith walked into the room, didn’t say a word, marched past the two men and got down on his knees.

“He delivered three to four quick punches into the side of the Afghan’s head … then two knees” to his chest and stomach area.

When the kneeing started, Person Seven said he yelled words to the effect: “Whoah whoah, what are you doing? We’re looking after this, get out of here.”

“At that point, he stood up walked out of the room, did not say a word,” the witness said.

Nicholas Owens SC, on behalf of the media outlets Mr Roberts-Smith is suing for defamation, asked if the use of force was warranted.

“I felt it was completely and utterly unnecessary,” Person Seven replied.

The Victoria Cross recipient has strenuously denied the allegation.

The 43-year-old is suing The Age, The Sydney Morning Herald and The Canberra Times over reports that he committed war crimes and murders in Afghanistan between 2006 and 2012.

‘Watch the life drain out of his eyes’

Days after the July 2012 death of Sergeant Blaine Flower Diddams who was killed during a battle in Afghanistan, Person Seven recalled Mr Roberts-Smith talking to him before deployment.

“Before this trip’s over, I’m going to choke a man to death with my bare hands,” Mr Roberts-Smith allegedly said.

“I’m going to look him in the eye and I’m going to watch the life drain out of his eyes.”

Person Seven said he responded that he was busy and they needed to “switch on” before the mission.

Later that year Person Seven said his patrol cleared more than 50 compounds and dozens of prisoners captured before Mr Roberts-Smith held one up by his shirt against a wall.

He punched the man four times, while a little girl was crying cradled in the arms of another detainee, he said.

Started to calm down

After Mr Roberts-Smith released the prisoner, the injured man picked up the child who had run to him and started to calm down.

Person Seven said Mr Roberts-Smith was glaring at the prisoner when he asked him what was going on.

“He’s a f***in bad c***,” he allegedly said, because the man hesitated when questioned what his daughter’s name was.

The witness was scrutinised about speaking to the media, as one of two soldiers who appeared as anonymous witnesses on the television program 60 Minutes.

Person Seven said the VC recipient had conducted an “aggressive intimidation and threatening campaign” against SAS soldiers taking part in a secret inquiry, and that serious allegations of war crimes needed to be aired.

He also accused Mr Roberts-Smith of relentlessly bullying a soldier dubbed Person One, recalling direct conversations in which he character assassinated, disparaged his performance, and called him a “coward,” contrary to what Person Seven says he viewed on the battlefield.

Person Seven denies he was motivated by jealousy that Mr Roberts-Smith had received the highest military honour for the 2010 battle of Tizak.

The trial continues.

– AAP