Pretoria, South Africa (CNN) -- A defense attorney Tuesday tried to poke holes in the highly emotional testimony of the first witness in the murder trial of Olympian double-amputee Oscar Pistorius, as another witness said she also heard screams the night model Reeva Steenkamp was killed. On the second day of the trial, testimony continued with the questioning of Pistorius' neighbor, Michelle Burger, who said Monday she was awakened by screams, followed by gunshots, when Pistorius shot and killed his girlfriend on Valentine's Day last year. Defense attorney Barry Roux attacked Burger's credibility, accusing her of using her husband's statement to craft her own.
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NEW: Second witness says she was awoken by shouting
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NEW: Husband of first witness also takes the stand Tuesday
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Pistorius shot and killed Reeva Steenkamp at his Pretoria home last year
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The double-amputee Paralympic and Olympic sprinter says he mistook her for a burglar
Paralympic
The case has fascinated South Africa and much of the world, with its high-profile defendant, the double-amputee track star so talented that he competed not only in the @placeholder but against able-bodied runners in the Olympics two years ago.
Barry Roux
She answered that she had clearly heard gunshots, testily answering @placeholder's questions about how much time had elapsed between them by saying she "didn't sit there with a stopwatch and take down the timing of each shot."
Reeva Steenkamp
Reeva Steenkamp
Pistorius pleaded not guilty Monday to one charge of murder and a firearms charge associated with Steenkamp's killing, as well as two gun indictments unrelated to @placeholder.
Oscar Pistorius
Pistorius
Pistorius
Pistorius
@placeholder also could get five years for each gun indictment and 15 years for the firearms charge.