South African Olympic sprinter Oscar Pistorius appears at the Magistrate Court in Pretoria on February 22, 2013. (ALEXANDER JOE/AFP/Getty Images)
A former girlfriend of Oscar Pistorius, breaking down twice on the witness stand Friday at his murder trial, described the double-amputee and Olympic sprinter as a man with a temper who was fond of guns.
The 27-year-old Pistorius is charged with premeditated murder in the fatal shooting of his girlfriend, Reeva Steenkamp, a 29-year-old model, on Valentine's Day last year.
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Pistorius maintains he had mistaken Steenkamp for an intruder at 3 a.m. when he fired four times through the bathroom door of his apartment. Prosecutors allege he intentionally killed her after an argument.
Samantha Taylor, 20, who was testifying on the 5th day of the trial in Pretoria, South Africa, said she began dating Pistorius when she was 17. She painted a picture of a man with a temper who had a gun with him "all the time."
Taylor, whose tearful testimony prompted the judge to call a brief recess twice, said Pistorius had cheated on her twice, once with Steenkamp, the South African Times Live reported.
Pistorius sat upright in the dock, listening to Taylor's testimony. At various times in the trial, he has appeared to weep and hold his head in his hands.
Taylor described one incident in which Pistorius and a friend, Darren Fresco, were stopped for speeding and Pistorius got into an argument with a police officer.
"Oscar and Darren were irritated and they said they wanted to shoot a robot," she testified. "About two minutes later, Oscar took out his gun and shot through the roof," Taylor told the court, adding that the sunroof was open at the time. Defense attorney Barry Roux has denied the incident.
The willowy blonde said Pistorius once confronted the driver of another car that had followed them home one night, holding his gun to the window of the car until the other person drove off.
Taylor also testified about Pistorius' habits, noting that at least twice he woke her during the night when he suspected there was an intruder in the apartment. She also said he always kept his gun on a table next to his side of the bed, never under the bed.
In the fatal shooting, Pistorius has said that he got his gun from under the bed and did not try to locate Steenkamp before firing into the bathroom.
The defense has also contended that witnesses who testified to hearing a woman's screams on the night of the killing were mistaken, and that they were actually hearing the high-pitched woman-like screams of Pistorius, after he had realized he had shot Steenkamp.
Taylor, however, said she has heard Pistorius scream in the past, at her and at others, and he did not sound like a woman.
"He sounds like a man," she told the court, according to Times Live.
Pistorius was born without fibula bones because of a congenital defect and his legs were amputated when he was 11 months old.
He has run on carbon-fiber blades and is a multiple Paralympic medalist. He also competed at the London Olympics but didn't win a medal.