A witness in the Oscar Pistorius trial has described hearing "bloodcurdling screams" on the night the Paralympian shot his girlfriend dead.
Michell Burger, who lived on the neighbouring estate to the Silverwoods Estate in Pretoria where Pistorius lived, described hearing a woman screaming followed by four gunshots on the night of model Reeva Steenkamp's death.
Her evidence came on the first day of Pistorius's highly-anticipated trial at the North Gauteng High Court in Pretoria today, where the six-times sprint champion formally pleaded not guilty to four charges including the murder of Steenkamp.
Prosecutors allege the 27-year-old shot model and reality TV star Steenkamp, 29, through the bathroom door of his home.
Burger, a neighbour of Pistorius who lives in the Silver Stream Estate, described waking up at around 3am to a woman's "terrible screams".
Speaking through an interpreter, she said: "We woke up from the screams. My husband jumped up and went to the balcony."
Ms Burger told the court it had been traumatic to hear the "bloodcurdling screams", adding: "It leaves you cold."
She said she also heard a man screaming for help, adding: "Three times he yelled for help."
Burger said she and her husband called security at their estate to report the screams and what they thought was a break-in.
She added: "I heard her screams again, it was worse, it was more intense. Just after her screams, I heard four shots, it was four gunshots that I heard."
Asked to describe the successive shots, she said there was a pause between the first and second which was longer between the second and third shots and the third and fourth.
She said: "I told my husband that I do not hope that that woman saw her husband being shot in front of her because after he screamed for help we didn't hear him again."
The start of the trial - which is being watched by the world - was delayed by an hour and a half today as the court waited for Afrikaans interpreters.
The double amputee is charged with the murder of Ms Steenkamp, whom he shot dead at his home on Valentine's Day last year.
Asked how he pleaded, he said: "Not guilty, my lady."
The Paralympic star, wearing a dark suit, white shirt and dark tie, entered not guilty pleas to four charges.
Pistorius, dubbed the "Blade Runner" for his prosthetic legs, admits shooting Miss Steenkamp dead at his home but claims he thought she was an intruder.
In court today, Pistorius, who was supported by family members including siblings Carl and Aimee and his uncle Arnold, came face to face with Steenkamp's mother June, who is attending the trial.
Prosecutor Gerrie Nel told the court: "They were the only two people in the house. There were no eyewitnesses.
"The state's case is based on circumstantial evidence."
He said evidence included what neighbours heard, and prosecutors would argue that "a certain inference" could be drawn from the scene.
"We argue that the accused's version in the bail application and today could not reasonably possibly be true, should be rejected," he said, adding: "The only inference from the circumstantial evidence would be that the accused shot and killed the deceased."
The court was read a statement from Pistorius in which he claimed he mistakenly thought there was an intruder in his home, leading him to open fire in an attempt to protect himself and Steenkamp.
The statement, read by Pistorius's defence lawyer while the athlete remained standing, said the scene had been contaminated and disturbed.
In it, the Paralympian said he did not intend to kill his then-girlfriend that night and they had not argued that night.
He said: "I deny this allegation in the strongest terms because there was no argument. The allegation that I wanted to shoot (or kill) Reeva cannot be further from the truth."
