The prosecutor in the Oscar Pistorius trial has begun probing Oscar Pistorius’s testimony, grilling him over the “terrible mistake” that resulted in Reeva Steenkamp’s death.

After Pistorius’s denial on Wednesday, prosecution lawyer Gerrie Nel began a searing cross-examination, immediately confronting Pistorius with the magnitude of his actions on February 14, 2013.

After Pistorius conceded he made a terrible “mistake”, Nel – nicknamed “the bulldog” for his tenacious courtroom performance – was incredulous.

“You made a mistake? You killed a person, that’s what you did!” he thundered.

“You shot and killed her, won’t you take responsibility for that?”

“You shot and killed her, won’t you take responsibility for that?”

Pistorius’s cross-examination is expected to be a key point in his trial, a stern test of both his version of events and of his resolve.

The 27-year-old Paralympian wrapped up three days of emotional and harrowing defence testimony by denying he wanted to kill girlfriend Reeva Steenkamp or the intruder he believed to be behind a toilet door in his home on the night of Valentine’s Day last year.

“I did not intend to kill Reeva, milady, or anyone else,” he told the murder trial, in his strongest rebuttal yet of charges against him.

Pistorius claims he mistook Steenkamp for an intruder.

He faces a life sentence if convicted of her murder.

But he could also face a murder charge if the prosecution shows he intended to kill when his life was not threatened – regardless of whether he knew who was behind the door.

‘It is a zombie stopper’

Prosecutor Gerrie Nel presented a Sky News report showing Mr Pistorius firing a gun at a shooting range with a voice thought to be Pistorius saying “it’s not as soft as brains but ****, it is a zombie stopper”.

The athlete agreed the voice was his but said he did not see the relevancy of the video, as the word “zombie”  was not referring to shooting a human.

Pistorius broke down again when shown a graphic picture of girlfriend Reeva Steenkamp’s head after the shooting.

“I don’t have to look at the picture,” Mr Pistorius said. “I was there.”

View the video below.

Getty

Earlier, Pistorius  gave a Pretoria court a dramatic description of how he tried to save his dying girlfriend, Reeva Steenkamp, after shooting her, saying he could feel her blood running down on him.

On the third day of his testimony on Wednesday, the double-amputee Olympic athlete answered questions from his defence lawyer about the chain of events on the night of February 14, 2013.

Pistorius had on Tuesday told the court he heard noise from the bathroom, thought a burglar had entered and fired four shots through the door. On realising Steenkamp could be inside, he then smashed the door with a cricket bat.

“As I entered the toilet I knelt over Reeva. She was sitting with her weight on top of the toilet bowl,” Pistorius said with a trembling voice – contradicting evidence presented by prosecution that Steenkamp had been standing in a defensive position behind the door.

“I checked to see if she was breathing. She wasn’t. I put my arms under her shoulders and sat there crying for some time. I had her head on my left shoulder. I could feel the blood was running down on me.

I put my arms under her shoulders and sat there crying for some time. I had her head on my left shoulder. I could feel the blood was running down on me.

“At some point, I heard her breathing,” Pistorius continued. He ran to the bedroom for his phone and called Johan Stander, the manager of the high-security estate where he lived in Pretoria.

“I was struggling to pick her up. She was struggling to breathe.”

Pistorius then called emergency services.

The athlete said he opened the front door, went back to the bathroom, and carried Steenkamp down the stairs.

June Steenkamp, mother of murdered model Reeva.

“I just sat with her and waited for the ambulance to arrive. I felt helpless, I wanted to take her to the hospital. I had my fingers in her mouth to help her breathe,” he said in tears.

He breathed deeply and sighed, while Steenkamp’s mother June sat expressionless.

When the emergency services came, “Reeva had already died while I was holding her.”

When a police officer then came and introduced himself, “I was unable to speak with him. I was sitting on the (kitchen) floor, crying.”

Pistorius is expected to testify for about a week, during which he will face tough questioning from prosecutor Gerrie Nel.

The trial has now lasted for 19 days and is expected to continue into May.

-with AAP