Pretoria, South Africa (CNN) -- Oscar Pistorius prosecutor Gerrie Nel wants the South African track star sent for independent psychiatric evaluation, he said Monday, in a move that could delay the athlete's murder trial for a month or more. A psychiatrist testified Monday that Pistorius has an anxiety disorder stemming from his double amputation as an infant and his unstable parents. He's depressed now and feeling guilt from having killed his girlfriend, Reeva Steenkamp, defense witness Dr. Meryl Vorster said on the stand. Nel responded by comparing the athlete's mental state to post-traumatic stress disorder and saying the law required psychiatric observation.
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NEW: Prosecutor Gerrie Nel says the law requires an evaluation of Pistorius
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A psychiatrist testified that he suffers general anxiety and is depressed
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She says he can tell the difference between right and wrong
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Pistorius says he mistook his girlfriend for an intruder in the middle of the night
Gerrie Nel
Nel
Gerrie Nel
@placeholder is due to submit his application on Tuesday after both sides have finished questioning Vorster.
Oscar Pistorius
Pistorius
Pistorius
Pistorius
His parents then put pressure on him to appear normal, and his mother abused alcohol at times after she and @placeholder' father divorced, she said.
Meryl Vorster
@placeholder also addressed the question of why Pistorius took his gun and went toward the sound of what the thought was danger rather than trying to get away.
Gerrie Nel
Nel
Gerrie Nel
@placeholder has fought aggressively to show that Pistorius argued with Steenkamp before killing her.