PRETORIA, South Africa — Oscar Pistorius wept today as his defense lawyer read the athlete's account of how he shot his girlfriend to death on Valentine's Day, claiming he had mistaken her for an intruder.

Prosecutors, however, told a packed courtroom that the double-amputee known as the Blade Runner intentionally and mercilessly shot and killed 29-year-old Reeva Steenkamp model as she cowered inside a locked bathroom.

Pistorius told the Pretoria Magistrate's Court at a bail hearing he felt vulnerable in the presence of an intruder inside the bathroom because he did not have his prosthetic legs on, and fired into the bathroom door.

In a major point of contention that has already emerged, prosecutor Gerrie Nel said Pistorius took the time to put on his prostheses, walked seven meters (yards) from the bed to the enclosed toilet inside his bathroom and only then opened fire. Three of the bullets hit Steenkamp of the four that were fired into the door, Nel said.

Pistorius said in his sworn statement that after opening fire, he realized that Steenkamp was not in his bed.