Murder-accused Paralympian Oscar Pistorius broke down in tears at the Pretoria High Court Wednesday as the prosecution started cross examining him.
He is being tried for killing his girlfriend Reeva Steenkamp on 2013 Valentine's Day.
Prosecutor Gerrie Nel showed the court a video footage of Pistorius shooting water melons during a shooting practice at a shooting range.
When one of the water melons exploded Pistorius is heard in the video shouting in excitement.
"You know the same happened to Reeva's head, it exploded.
"Am I correct in saying that your shooting at a watermelon was to see what the effect would be if you shoot somebody in the brain? " Nel asked Pistorius after showing the video.
When Pistorius denied the allegation, Nel showed a graphic picture of Reeva's bleeding head wound. He then challenged Pistorius to look at the picture.
"I remember ... my fingers touched her head, I do not have to look at a picture," Pistorius replied while breaking down in tears.
Pistorius's defence lawyer Barry Roux objected to Nel's questioning to which Judge Thokozile Masipa agreed.
Masipa briefly adjourned the court to give Pistorius time to calm down.
When the trial resumed, Pistorius told the court that he pleaded not guilty to the charge of murder because he was being accused of something that did not happen.
He said that he shot Reeva by mistake while taking her for some intruder when he heard noise in the toilet.
Nel asked Pistorius if his gun went off accidentally when he fired four shots through a locked toilet door.
Pistorius answered in an emotional voice, "When I fired ... I believed that someone was coming out of the toilet to attack me ... I didn't have time to think about what was happening ... I believed that my life was in danger ... when I heard a noise I didn't have time to think. Before thinking, out of fear, I had fired four shots."
Pistorius went on to tell the court that he was careful with his answers because his life was on the line.
Pistorius is also facing three more charges of contravening the fire arms act.
In the 2012 London Olympics Pistorius became the first double- leg amputee to participate in Olympics alongside able-bodied athletes when he competed in the men's 400 metres and 4X400 metres relay races.
He has been a poster hero for several companies. At the time of the shooting he was earning an average of $two million a year.
