Oscar Pistorius sobs as he's charged with premeditated murder of girlfriend Reeva Steenkamp

Updated at 7:19 a.m. Eastern

PRETORIA, South Africa Olympian Oscar Pistorius fired into the door of a small bathroom where his girlfriend was cowering after a shouting match on Valentine's Day, hitting her three times, a South African prosecutor said Tuesday as he charged the sports icon with premeditated murder.

If convicted of the crime, correspondent Emma Hurd reports for CBS News that Pistorius could spend the rest of his life in prison. The prosecution claims Pistorius deliberately shot at his girlfriend four times in a rage during a Valentine's Day argument. They say he should remain in custody until his trial begins.

In an affidavit revealed during the bail hearing, Pistorius said he was "absolutely mortified" over his girlfriend's death, and that he shot through the door thinking it was a burglar on the other side who had broken into his home through the bathroom window. He claims he then broke down the door with a cricket bat.

Pistorius sobbed softly as his lawyer insisted that Reeva Steenkamp's shooting was an accident.

"She couldn't go anywhere. You can run nowhere," prosecutor Gerrie Nel said at a bail hearing.

The shooting death has shocked South Africans and many around the world who idolized Pistorius for overcoming adversity to become a sports champion, competing in the London Olympics last year in track besides being a Paralympian. Steenkamp, 29, was a model and law graduate who made her debut on a South African reality TV program on Saturday, two days after her death.

Nel said the couple had had a shouting match and Steenkamp fled to the bathroom, down a seven-yard passage from the bedroom, and locked herself in. He said the 26-year-old Pistorius got up from bed and had to put on his prosthetic legs to reach the toilet door.

Nel told the court the door was broken open after the shots were fired. Pistorius' lawyer insisted there was no evidence to substantiate a murder charge.

"Was it to kill her, or was it to get her out?" defense attorney Barry Roux asked the court, referring to the browken-down door. "We submit it is not even murder. There is no concession this is a murder."

Pistorius, who had appeared grim and solemn at the start of the hearing, broke down and sobbed softly with his head in his hands as his lawyer argued that he had mistaken Steenkamp for a burglar. The shooting in the early hours of Feb. 14 came after neighbors had heard a loud argument and then gunshots, police have said. The couple had been dating for only about three months.

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As details emerged at the dramatic court hearing in the capital, Steenkamp's body was being cremated Tuesday at a memorial service in the south-coast port city of Port Elizabeth. The family said members had arrived from around the world. Six pallbearers carried her coffin, draped with a white cloth and covered in white flowers, into the church for the private service.

June Steenkamp, the mother, said the family wants answers.

"Why? Why my little girl? Why did this happen? Why did he do this?" she said in an interview published Monday in The Times newspaper.

At the court, Nel said the killing was premeditated because Pistorius had planned to say that he thought he was shooting an intruder, and had told that story to his sister, Aimee.

"It was all part of the preplanning. Why would a burglar lock himself inside the bathroom?" Nel asked. The shooting happened at Pistorius' home in a guarded and gated community in a luxury suburb of Pretoria.

Roux, in arguing that Pistorius should be freed on bail, he said there were no other charges outstanding against the double-amputee who last year became the first double-amputee track athlete to run at the Olympics.

Legal experts say it could take months for the case to be tried.

Pistorius, in a gray suit and tie, nodded after the chief magistrate asked if he was well. And he nodded his appreciation when his brother, Carl, pressed his shoulder in support. Journalists jammed into the courtroom, which was full with almost 100 people, including Pistorius' father, Henke, and sister Aimee.

In an email to The Associated Press on Monday, Pistorius' longtime track coach — who was yet to comment — said he believes the killing was an accident.

"I pray that we can all, in time, come through this challenging situation following the accident and I am looking forward to the day I can get my boy back on the track," Ampie Louw wrote in his statement. "I am still in shock following the heart-breaking events that occurred last week and my thoughts and prayers are with both of the families involved."