PRETORIA, South Africa (AP) -- Oscar Pistorius broke down in sobs and howls while testifying at his murder trial Tuesday, forcing the court to adjourn as the star athlete was describing the moments he said he first realized he had shot girlfriend Reeva Steenkamp through a toilet door in his home last year.
"I sat over Reeva and I cried," Pistorius said, telling how he broke open the stall door in his bathroom to discover his mortally wounded girlfriend inside and slumped over in the cubicle. "I don't know how long I was there for," Pistorius said.
Pistorius has said he shot Steenkamp after mistaking her for an intruder in his bathroom. Tuesday marked the first time he has spoken publicly on the details of the shooting. Prosecutors call Pistorius' story an intricate lie and maintain he intentionally killed his girlfriend, a model and reality TV show star, after an argument.
On the witness stand, he began to cry loudly, forcing the judge to rule a brief adjournment. Pistorius didn't stand up when the judge left, and also started to wail as he sat slumped over on the witness stand, his head in his hands. His brother and sister went over to him in an apparent attempt to comfort him and he left the courtroom through a side door, still crying.
When Judge Thokozile Masipa returned, she called an early adjournment. Pistorius had by that time appeared to compose himself and had returned to sit, jaw clenched, in the witness box.
Pistorius was testifying about how he broke down the toilet door after shooting four times through it, and finding a gravely injured Steenkamp inside.
"At that point all I wanted to do was just look inside to see if it was Reeva," Pistorius said, his voice shaking and starting to cry before breaking down in the sobs.
The Olympian is charged with premeditated murder in Steenkamp's death and faces a life sentence with a minimum of 25 years before parole if convicted on that charge.
Earlier, Pistorius said that the sound of a bathroom window opening had convinced him that someone was breaking into his house.
"That's the moment that everything changed," Pistorius said.
Oscar Pistorius described Tuesday what he said were the terror-filled moments before he shot Steenkamp to death and removed his prosthetic legs in court to show how he stood by the toilet door which he fired into. The actual bullet-riddled toilet door was set up in the courtroom to show how the shooting took place.
Pistorius said that he heard a window open in his bathroom in the early hours of Feb. 14, 2013, causing him to believe intruders had entered his house and to race to get to his gun to defend himself and his girlfriend, who he claims he thought was still in bed.
Pistorius claims he was not wearing his prosthetics -- and therefore felt more vulnerable -- when he shot through the door to kill Steenkamp. In the courtroom, he sat on a wooden bench and took off his prosthetics and approached the bullet-marked toilet door to show his diminished height.
Pistorius is charged with premeditated murder in Steenkamp's death and faces a life sentence with a minimum of 25 years before parole if convicted on that charge.