The fifth day of Oscar Pistorius’ trial in South Africa has begun with his ex-girlfriend Samantha Taylor telling the court the athlete once fired his gun from his car sunroof after becoming angry with police.

Earlier, Samantha Taylor broke down while discussing two breakups with the athlete.

Samantha Taylor said Oscar Pistorius had twice been unfaithful, with the relationship finally ending when he “cheated” on her with Reeva Steenkamp.

Oscar Pistorius denies both murdering Reeva Steenkamp and the alleged shooting incident.

The defense also pointed to emails it said proved the relationship with Samantha Taylor was already over by the time Oscar Pistorius began seeing Reeva Steenkamp.

Samantha Taylor insisted the relationship was not “officially” over when he started dating Reeva Steenkamp.

She also said the alleged shooting incident happened when he became angry after a police officer stopped him for speeding, saw the gun on the car seat and told him it could not be left there.

Samantha Taylor insisted her relationship with Oscar Pistorius was not officially over when he started dating Reeva Steenkamp (photo Getty Images)

Samantha Taylor accepted that he laughed around the time he actually fired the gun.

She testified that Oscar Pistorius kept his gun “on him all the time,” and described him as a man who could get very angry.

On Wednesday, the court heard evidence from boxer Kevin Lerena, about another incident in which Oscar Pistorius is alleged to have fired a gun – in a restaurant – after it was passed to him by another friend in the group. He said Oscar Pistorius asked the gun’s owner to take the blame.

Towards the end of Samantha Taylor’s evidence on Friday, the court was adjourned a second time when she broke down again in the witness box.

After returning, she was asked by the prosecution if there had been other occasions when Oscar Pistorius thought there was an intruder in his house.

Samantha Taylor replied that it had happened at least twice. Crucially, she said he always woke her up before taking his gun with him to check.

Oscar Pistorius claims that he shot Reeva Steenkamp after mistaking her for an intruder.

If found guilty, Oscar Pistorius, 27, could face life imprisonment.

Friday’s trial began with more testimony from neighbor Johan Stipp, who on Thursday told the court he found Oscar Pistorius praying over Reeva Steenkamp’s body as she lay dying.

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