At the start of closing arguments in his murder trial, Oscar Pistorius has been accused of being a “deceitful witness” who dropped the “baton of truth”.

Prosecutor Gerrie Nel began his concluding remarks on Thursday, with the defense due to follow on Friday.

Oscar Pistorius denies murdering his girlfriend Reeva Steenkamp.

The South African athlete says he mistook her for an intruder, but the prosecution says he deliberately shot her after a row.

Reeva Steenkamp was killed at Oscar Pistorius’ home in Pretoria on February 14, 2013.

The long-running trial was adjourned last month ahead of closing arguments.

Oscar Pistorius denies murdering his girlfriend Reeva Steenkamp (photo Reuters)

At the court in Pretoria, Gerrie Nel began his closing argument by accusing the athlete’s lawyers of presenting two lines of defense that “can never be reconciled”.

Oscar Pistorius, 27, said he had fired both involuntarily and also out of fear, Gerrie Nel argued, insisting the court had to choose only one of his defenses.

He said the court “should have no difficulty in rejecting” the athlete’s version of events because it was “devoid of any truth”.

Gerrie Nel also attacked Oscar Pistorius for presenting himself as “a victim of circumstance”.

Oscar Pistorius’ estranged father, Henke, was in the packed courtroom for the first time during the trial. It was also the first time that Barry Steenkamp, Reeva’s father, had attended.

The prosecution is convinced Oscar Pistorius gave conflicting accounts of how and why the double amputee shot Reeva Steenkamp four times through his toilet door.

Judge Thokozile Masipa is now likely to intervene more and her questions could well provide hints about a future verdict.

Oscar Pistorius’s lawyer, Barry Roux, will give his closing remarks after Gerrie Nel, in what correspondents say is the final showdown between two of South Africa’s top legal minds.

The judge is expected to adjourn the trial after hearing the arguments to consider her ruling, a process that analysts say will take in between a week to a month.

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