Oscar Pistorius
South African Olympic and Paralympic sprinter Oscar Pistorius arrives in court for the closing arguments of his trial at the North Gauteng High Court in Pretoria, August 7, 2014. Pistorius is on trial for murdering his girlfriend Reeva Steenkamp at his suburban Pretoria home on Valentine's Day last year. Reuters/Werner Beukes/Pool

Oscar Pistorius’ murder trial resumed Thursday at the North Gauteng High Court in Pretoria with state prosecutor Gerrie Nel branding the South African Olympian a “deceitful witness,” and insisting that he deliberately shot and killed his 29-year-old girlfriend, Reeva Steenkamp, at his home on Valentine’s Day last year.

Nel reportedly said, during his closing arguments, that Pistorius’ testimony was “devoid of any truth” and that he had presented conflicting accounts of the incident to the court. The double-amputee, who is nicknamed “Blade Runner,” has admitted to fatally shooting Steenkamp through a locked bathroom door but claims he mistook her for an intruder.

"The court will have to reject his evidence. The court must have a credible version from the accused," Nel reportedly told the Pretoria court during his closing arguments. "The court should have no difficulty in rejecting his full version of events, not only as not reasonably possibly true, but in essence as being absolutely devoid of any truth."

During the five-month long trial, the defense has reportedly portrayed Pistorius as a "highly-vulnerable individual," while the prosecution has said that the sprinter was an angry, jealous and gun-obsessed boyfriend with a violent past.

Nel reportedly criticized various defense witnesses stating that some of them gave the worst testimony he had ever seen in court. And, the defense was reportedly unable to prove claims that the Olympic gold-medalist could sound like a woman while screaming and that a blow from a cricket bat sounds like a gunshot.

Pistorius’ father, Henke, was present in the court on Thursday for the first time since the trial began in March, while Steenkamp's father, Barry, was also present.

Throughout the trial, the courtroom witnessed Pistorius sobbing, praying and vomiting; cross examinations of former police Col. G.S. van Rensburg by the defense, which revealed investigators mishandled evidence at the crime scene; Pistorius psychiatric evaluation; and, evidence from the prosecution that Pistorius has a questionable history with guns.

“If the accused’s version about what happened that night is rejected, it means there was no perceived intruder whatsoever,” Nel reportedly said.

Both the prosecution and the defense have submitted their final-argument documents to Judge Thokozile Masipa.

On Friday, the defense will make its closing remarks, following which the fate of Pistorius will be decided. If convicted, Pistorius could face premeditated murder charges, which carries a mandatory life sentence of 25 years.