A defense attorney tried to poke holes in highly emotional testimony Tuesday of the first witness in the murder trial of Olympian double-amputee Oscar Pistorius.

Testimony continued with the questioning of Pistorius' neighbor, Michelle Burger, who said in Monday's first day of testimony that she was awakened by screams, followed by gunshots, when Pistorius shot and killed his girlfriend, model Reeva Steenkamp, on Valentine's Day last year. On Tuesday, defense attorney Barry Roux attacked Burger's credibility, accusing her of using her husband's statement to craft her own.

Paragraph by paragraph, Roux pointed out similarities between their two statements. Burger repeatedly explained that the statements were similar because they both heard the same thing. "I'm as honest as I can be to the court," she said.

Pistorius has admitted he killed Steenkamp but pleaded not guilty Monday, saying that he mistakenly believed he was shooting a burglar. He only realized after firing four shots that his girlfriend was not in bed but in the bathroom he was firing at, his defense team said on his behalf Monday.

Burger broke down in court when she described Steenkamp's screams. Through her tears, she said, "It was awful to hear her screams."

At one point, Pistorius clutched his head in his hands as an expert described how bullets struck Steenkamp's head.

On Monday, Burger testified that, "Something terrible was happening at that house. She called the shouts and screams "petrifying."

Finally, after brief questioning by prosecutor Gerrie Nel, Burger was excused.

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 Paralympics but against able-bodied runners in the Olympics two years ago.

Burger lives several hundred yards from where the killing took place.

During Nel's questioning Monday, Burger told the court that she heard a woman's screams and a man yelling for help.

"Just after 3, I woke up from a woman's terrible screams," she said. "Then I also heard a man screaming for help. Three times he yelled for help."

She assumed a nearby home was being invaded by criminals.

She later told her husband that she feared the woman had witnessed her husband being shot "because after he screamed, we didn't hear him."

Roux spent hours hammering Burger with questions in Monday's cross-examination, asking repeatedly if there could have been shots before she woke up, if she was sure about the sequence of events and about her knowledge of guns.

He asked if the "bang" sounds she heard might not have been gunshots, but rather a cricket bat bashing at a bathroom door.

She answered that she had clearly heard gunshots, testily answering Roux's questions about how much time had elapsed between them, saying she "didn't sit there with a stopwatch and take down the timing of each shot."

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