trial of blade runner Oscar Pistorius. The paralympic champ is charged with murdering his girlfriend reeva steenkamp and hamish Macdonald is live in Pretoria with the latest chilling testimony.... See More
trial of blade runner Oscar Pistorius. The paralympic champ is charged with murdering his girlfriend reeva steenkamp and hamish Macdonald is live in Pretoria with the latest chilling testimony. Hamish. Reporter: George, it's an intense atmosphere in the courtroom. The proceedings were brought to a halt temporarily because one south african broadcaster put on television an image of a witness. Now, the court guaranteed that wouldn't happen. So the judge was pretty angry. But that was not the only drama this morning. In court emotions are running high this morning. When I'm in the shower -- Reporter: His neighbor a university professor living 200 yards away says she was woken by blood-curdling creams in the early hour of Valentine's day that coincides with the shooting of Oscar's model girlfriend reeva steenkamp. This witness chose not to appear on camera. Just before the gunshots, it was blood-curdling. You just know that a woman's life was really threatened. Reporter: The prosecution claims there was an argument. That steenkamp fled to the bathroom with two cell phones in fear. The neighbor seems to support that idea. Why did you decide then already it's not true, it's not right. It could not have been an intruder. Moments before the shots were fired she had petrifying screams. I heard that female screaming fearfully. Reporter: During cross-examination the Pistorius defense team asks if there's any chance it was Oscar's screams she heard. Mistaking it for a woman's voice. I can say yes I heard her screaming. Reporter: The defense team claims Pistorius used a cricket bat to beat down the bathroom door. Is it possible too the neighbor heard this and confused it with gunshots. If the answer is yes, you say yes, if it's no, you say no. If you don't know, you say I don't know. If you don't remember, you say I don't remember. Otherwise, you will be in that witness box for another day and maybe two more or the day thereafter. Reporter: Pistorius says he acted in self-defense thinking an intruder was inside the house. He had no idea he was shooting his girlfriend. How do you plead? Not guilty, my lady. Reporter: Robin, don't forget the prosecution alone has called 107 witnesses so this has a long way to go yet. Right now there's another witness in the stand, a neighbor who lived even closer who is telling much the same story of loud screams and bang-bang. Very chilling.
This transcript has been automatically generated and may not be 100% accurate.