Olympic hero Oscar Pistorius fired four shots at Reeva Steenkamp through his bathroom door after she had locked herself in, a South African court has heard.

At the start of Pistorius's bail hearing at Pretoria Magistrates' Court, prosecutor Gerrie Nel pursued the case of premeditated murder against the athlete, arguing that his claim of mistaken identity was all part of the plan.

Refuting the defendant's claim that he mistook his girlfriend for a burglar, Nel alleged that Steenkamp had arrived at Pistorius's house between 5 and 6pm on the night of the shooting, around nine hours before the incident took place.

The court was told that Steenkamp had planned to stay the night, having packed overnight and cosmetics bags.

Nel said: "The accused shot and killed an unarmed innocent woman. [He] fired four shots, three killed the woman. She locked herself in the bathroom and he shot through the door."

According to the prosecution, Pistorius had to put on his prosthetic legs and walk seven metres from his bed to his bathroom door before he began firing - suggesting the shooting was not spontaneous. Furthemore, the fact that the door was locked indicates Steenkamp was trying to protect herself from her boyfriend, Nel said.

"It was 0300 in the morning, a woman in the toilet. If she was there for an urge, why did she lock the door?" Nel asked the court.

The prosecution claimed that premeditation did not necessarily require days or months of planning - anyone who approaches their target, aims a gun and fires is committing a premeditated murder.

However Pistorius's lawyer, Barry Roux, said that by Nel's logic anyone who shoots a burglar in the heat of the moment is carrying out a premeditated offence.

Roux suggested Pistorius could easily have mistaken Steenkamp for an intruder because burglars often hide in toilets after breaking into properties. According to the defence, the broken toilet door does not imply guilt - Pistorius shot through the door, then broke through it when he realised his mistake.

Roux asked "His [Nel's] case is she was shot through the bathroom door. Why would you then break open the door?"

When Roux claimed Pistrius did not know whether the person in the toilet was Steenkamp, the defendant began to sob uncontrollably.

The trial continues, IBTimes UK will bring news of the verdict as soon as it is delivered.

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