The murder trial of Oscar Pistorius has wrapped up with the prosecution making a final plea for the South African athlete to "face the consequences" of shooting dead his girlfriend Reeva Steenkamp.

Judge Thokozile Masipa will now analyse more than 4,000 pages of evidence before delivering her verdict on 11 September.

Mr Pistorius, 27, is accused of murdering Ms Steenkamp, a law graduate and model, at his home in Pretoria on Valentine's Day last year.

The defence says Mr Pistorius shot Ms Steenkamp through a locked toilet door in self-defence, believing she was an intruder, and that therefore he should be acquitted.

State prosecutor Gerrie Nel has spent the trial portraying Mr Pistorius as a gun-obsessed hothead who deliberately shot Ms Steenkamp, 29, four times as she was taking refuge in the toilet after an argument.

Cutting through months of complex evidence and testimony, Mr Nel ended proceedings by returning to his core argument.

"He knew there was a human being in the toilet. That's his evidence," Mr Nel told the judge.

"His intention was to kill a human being. He's fired indiscriminately into that toilet. Then m'lady, he is guilty of murder. There must be consequences."

Defence lawyer Barry Roux said during his own wrapping-up that psychological evidence had proven the track star had a heightened fight response because of his disability and was in a terrified and vulnerable state when he shot Ms Steenkamp.

"You're standing at that door. You're vulnerable. You're anxious. You're trained as an athlete to react. Take all those factors into account," Mr Roux said, adding that Mr Pistorius had felt exposed because he was standing on the stumps of his legs.

"He stands with his finger on the trigger, ready to fire when ready. In some instances a person will fire reflexively," he added. "That is your primal instinct."

Mr Roux also argued that prosecutors had only called witnesses who supported their argument and not other key people, including police officers, who he said would have undermined their case.

Yesterday, Mr Nel said Mr Pistorius had told "a snowball of lies" and had called for the track star to be convicted of intentional murder, a crime that could land him with a life sentence.

A potential lesser charge of culpable homicide - comparable to manslaughter - could carry a sentence of about 15 years.

Mr Pistorius also faces three separate charges, including two counts of discharging firearms in public and possession of illegal ammunition, all of which he denies.

To arrive at a verdict, Judge Masipa and her two assistants will have to weigh up the credibility of testimony on both sides, including that of Mr Pistorius.

In the absence of a jury, experts say the crux of the case is whether Judge Masipa accepts or rejects his version of events.

Mr Nel has called for Pistorius' evidence thrown out because it was "devoid of any truth" and the athlete contradicted himself when he said during cross-examination that he fired both accidentally and deliberately.

Mr Roux said the trial should only ever have been on the charge of culpable homicide, rather than murder, because he said Mr Pistorius had clearly shot Ms Steenkamp by mistake.

Mr Nel and Mr Roux have focused much of their closing arguments on evidence from witnesses who say they heard a woman scream before a volley of shots, supporting the prosecution's position that the couple had an argument before Ms Steenkamp was killed.

Mr Roux went through the early morning of the shooting minute-by-minute during his wrapping-up, arguing that the witnesses were confused and contradictory about the sounds they heard.

He also spent time analysing photos he said proved the police had moved items in the couple's bedroom, countering a key claim by Mr Nel that images of the room proved that Mr Pistorius' version of the events was impossible.