(CNN) -- Oscar Pistorius was the target of relentless and combative questioning Wednesday as the prosecutor in his murder trial tried to rattle the runner about the night he shot dead his model girlfriend. Vowing to "get to the truth" of the events that took place on Valentine's Day last year, prosecutor Gerrie Nel began a blistering cross-examination of the Olympic sprinter in the case that has gripped South Africa. "You shot and killed her. Say it -- 'I shot and killed Reeva Steenkamp,'" Nel told Pistorius. The prosecutor immediately boxed the double-amputee athlete into a corner in what his defense team described as an "ambush," by asking him about a video showing Pistorius shooting a watermelon at a gun range.
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Prosecution shows video of Pistorius at shooting range
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Prosecution seeking to highlight discrepancies in Pistorius affidavit, testimony
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Steenkamp struggled to breathe, Pistorius says
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Trial was adjourned Tuesday after the athlete broke down crying
"I was there, I don't have to look at a picture," @placeholder snapped, sobbing.