Pistorius: I didn't consciously pull trigger

• The prosecution ends its five-day cross-examination of Pistorius


• Pistorius says he's not sure who's to blame for shooting Reeva Steenkamp


• The prosecution is trying to prove Pistorius killed his girlfriend intentionally


• The double amputee insists that he mistook Reeva Steenkamp for an intruder

(CNN) -- After several days of intense grilling, the prosecution ended its cross-examination in Oscar Pistorius' murder trial.

Pistorius cried and his voice trembled during his testimony as prosecutor Gerrie Nel challenged his account of what happened the night he shot and killed his girlfriend, Reeva Steenkamp.

On Tuesday, the prosecutor asked who should be blamed for shooting Steenkamp.

"I'm not sure, my lady," Pistorius said, directing his answer to the judge. He repeatedly said he feared for his life and thought there was an intruder in his bathroom.

A day earlier, Pistorius testified, "I blame myself for taking Reeva's life."

At times Pistorius cried and his voice cracked as he described finding his girlfriend slumped over after shooting her.

"I was saying, 'Baby hold on. Jesus, please help me,'" he said Tuesday.

Nel has accused the double-amputee sprinter of "tailoring" his version of events to suit his story.

Nel, known in South African legal circles for his bulldog-like approach to questioning, has gone through minute detail regarding the early hours of Valentine's Day 2013.

The prosecution's argument is that Pistorius shot Steenkamp intentionally after a heated argument. Pistorius does not deny shooting her but insists that he mistook her for an intruder.

READ: Gerrie Nel: 'Bulldog' prosecutor sinks teeth into Oscar Pistorius at murder trial

READ: Oscar Pistorius says he never picked on Reeva Steenkamp

CNN's Marie-Louise Gumuchian contributed to this report.