Story highlights Pathologist tells court that any of Steenkamp's three injuries could have been fatal

Defense lawyer challenges security guard's statements

Pistorius says he mistook Steenkamp for an intruder

One prosecution witness may bolster the defense case

"Blade Runner" Oscar Pistorius broke down and vomited in court Monday as he heard a pathologist testify about his girlfriend Reeva Steenkamp's injuries after he shot her dead on Valentine's Day last year.

The testimony of pathologist Gert Saayman was interrupted by Pistorius' sobbing and retching, leading to a pause in the proceedings.

Earlier, Judge Thokozile Masipa imposed a broadcast blackout on Saayman's testimony. Masipa, who has been presiding over the weeklong trial in Pretoria, extended the ban to live reporting on Twitter.

Pistorius admits he shot Steenkamp, 29, but says that it was a tragic case of mistaken identity and that he thought she was an intruder who had broken into his home.

In court, Saayman confirmed that Steenkamp died from multiple gunshot wounds, consistent with having been hit in the head, arm and hip by three shots fired through the locked door of a toilet cubicle.

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Photos: Photos: Oscar Pistorius murder trial Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Oscar Pistorius reaches out to his uncle Arnold Pistorius and other family members as he is led out of court in Pretoria, South Africa, after being sentenced to five years in prison on Tuesday, October 21. Pistorius, the first double-amputee runner to compete in the Olympics, was sentenced for culpable homicide in the February 2013 death of his girlfriend, Reeva Steenkamp. Hide Caption 1 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius leaves the high court in Pretoria on Monday, October 13. A judge cleared Pistorius of premeditated murder last month, but he was found guilty of culpable homicide -- the South African term for unintentionally, but unlawfully, killing a person. Hide Caption 2 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius speaks with his uncle Arnold Pistorius during his trial at the Pretoria High Court on Friday, September 12. Hide Caption 3 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius cries on the stand in Pretoria on Thursday, September 11, as the judge reads notes while delivering her verdict. Hide Caption 4 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius arrives at court on September 11. Hide Caption 5 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius speaks to someone in court as his murder trial resumes in Pretoria on Thursday, August 7. Hide Caption 6 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius sits in court in Pretoria on Tuesday, July 8. Hide Caption 7 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius arrives at court in Pretoria on Monday, July 7. Hide Caption 8 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius yawns during day 37 of his murder trial on June 3. Hide Caption 9 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius hugs a supporter Wednesday, July 2. Hide Caption 10 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius listens to evidence being presented in court on Monday, June 30. Hide Caption 11 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius leaves the court in Pretoria on Tuesday, May 20. Hide Caption 12 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius reads notes during his trial on Monday, May 12. Hide Caption 13 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Ballistics expert Tom "Wollie" Wolmarans testifies for the defense on May 12. Hide Caption 14 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – A red laser dot points at bullet holes in the bathroom door for a forensic demonstration during the trial on May 12. Pistorius admits firing four bullets through the closed door, killing Steenkamp, but says he thought he was protecting himself from a burglar. Hide Caption 15 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius returns to court as his murder trial resumes Monday, May 5, after a break of more than two weeks. Hide Caption 16 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius gets a hug from a woman as he leaves court in Pretoria on Wednesday, April 16. Hide Caption 17 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius rubs his eye Tuesday, April 15, after testifying during his murder trial. Hide Caption 18 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius arrives at the court in Pretoria on Monday, April 14. Hide Caption 19 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius' sister, Aimee, cries in court as she listens to her brother's testimony on Tuesday, April 8. Hide Caption 20 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – June Steenkamp, Reeva Steenkamp's mother, reacts as she listens to Pistorius' testimony on April 8. Hide Caption 21 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius is hugged by his aunt Lois Pistorius in court on Monday, April 7. Hide Caption 22 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius sits inside the courtroom as members of his defense team talk in the foreground Friday, March 28. Hide Caption 23 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius leaves court on March 28. The trial was delayed until April 7 because one of the legal experts who will assist the judge in reaching a verdict was sick. Hide Caption 24 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Steenkamp's mother, right, and family friend Jenny Strydom react in court Tuesday, March 25, during cross-questioning. Hide Caption 25 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Cell phone analyst Francois Moller testifies during the trial on March 25. Questioned by the prosecution, Moller listed in order the calls made and received by Pistorius after he shot Steenkamp. Hide Caption 26 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius cries as he sits in the dock during his trial on Monday, March 24. Hide Caption 27 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius talks to defense attorney Barry Roux on March 24. Hide Caption 28 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius holds his head while members of his family talk behind him on Tuesday, March 18. Hide Caption 29 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Steenkamp's mother, wearing the white collared shirt, looks on while a police officer takes notes in court March 18. Hide Caption 30 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius is hugged by his aunt Lois on March 18. Hide Caption 31 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius takes notes Monday, March 17, as his murder trial enters its third week. Hide Caption 32 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius covers his head as he listens to forensic evidence Thursday, March 13. Hide Caption 33 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Forensic investigator Johannes Vermeulen, left, is questioned during the trial March 13. Hide Caption 34 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius listens to questions during his trial on Wednesday, March 12. Hide Caption 35 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – A police officer takes part in a court reconstruction March 12. A police forensic expert said Pistorius was on the stumps of his amputated legs when he knocked down a locked toilet door with a cricket bat to reach his shot girlfriend. That counters the track star's assertion he was wearing his prosthetic legs at the time. Defense attorney Barry Roux countered by suggesting that even with his prosthetic legs on, Pistorius would not be swinging a bat at the same height as an able-bodied person. Hide Caption 36 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius listens to cross-questioning on Monday, March 10. Hide Caption 37 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Friends of Steenkamp's family watch Pistorius during his trial on March 7. Hide Caption 38 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius covers his ears on Thursday, March 6, as a witness speaks about the morning Steenkamp was killed. Hide Caption 39 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius' sister, Aimee, right, speaks with members of Steenkamp's family on March 6. Hide Caption 40 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius sits in court on the third day of his trial Wednesday, March 5. Hide Caption 41 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius appears on the second day of his trial Tuesday, March 4. Hide Caption 42 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Members of the media work during a break in proceedings March 4. Hide Caption 43 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius talks with Roux inside the court on March 4. Hide Caption 44 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius speaks with his legal representatives on March 4. Hide Caption 45 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius is escorted out of the court Monday, March 3, after the first day of his murder trial. Hide Caption 46 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – People try to get a glimpse of Pistorius as he leaves the court building on March 3. Hide Caption 47 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius is seen shortly after arriving for his trial on March 3. Hide Caption 48 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius walks into the courtroom on March 3. Hide Caption 49 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius takes a drink of water March 3 during his trial. Hide Caption 50 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – The case has captivated South Africa. Here, Lauren Wentzel watches the proceedings from her home outside Cape Town on March 3. Hide Caption 51 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – June Steenkamp arrives at the court building for the start of the trial. Hide Caption 52 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – Pistorius' relatives wait inside the courtroom on March 3. Hide Caption 53 of 54 Photos: Photos: Oscar Pistorius murder trial Oscar Pistorius murder trial – People at the court building wait for Pistorius' arrival on March 3. Hide Caption 54 of 54

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Pistorius appeared deeply physically distressed throughout the testimony, repeatedly making retching sounds and clutching his head in his hands. The track star, 27, appeared at times to try to cover his ears by clasping his hands behind his neck, or he put his fingers in his ears. His brother and sister came to check on him during the brief break in Saayman's testimony.

Security guard on the stand

Saayman said any of the three injuries to Steenkamp could have been fatal and all immediately incapacitating. He said it was probably the bullet to the skull that killed her almost immediately. It passed from the top of her head over her right eye to the base of her skull, suggesting that she was not standing when hit, he added.

Saayman said the wounds were consistent with "ranger" bullets, which open up "like the petals of a flower" to cause maximum tissue damage.

Earlier on Monday, defense lawyers challenged a security guard's statements about what happened on the night. Guard Pieter Baba said he talked by phone to Pistorius the night of the killing and Pistorius said "everything's fine" or "everything's OK."

But defense lawyer Barry Roux said Pistorius had said, "I'm fine."

Baba was adamant, saying, "What I just told the court is the truth."

Baba's testimony proceeded slowly because all questions and answers had to go through a translator. He gave two statements to police, months apart.

On Friday, Baba said he could hear Pistorius was crying and he knew everything was not fine.

Baba arrived at the house in time to witness Pistorius coming down the stairs carrying Steenkamp.

"I was so shocked, I couldn't think for a few moments," he testified.

Pistorius has pleaded not guilty to one charge of murder and a firearms charge associated with Steenkamp's killing as well as two gun indictments unrelated to her death.

Gun at his bedside

Another witness who testified Friday, former Pistorius girlfriend Samantha Taylor, said their relationship ended when he cheated on her with Steenkamp.

Prosecutor Gerrie Nel asked Taylor if she was ever at Pistorius' house when he thought there was an intruder. Taylor said yes.

She said Pistorius once heard something hit a bathroom window and woke her up to ask if she'd heard it, too, before taking his gun and going to investigate. Taylor said Pistorius woke her up other times when he thought he'd heard a noise.

Taylor also testified that Pistorius slept with a pistol on his bedside table or on the floor beside his prosthetic legs and once became so angry after a traffic stop that he shot a gun through the sunroof of a car.

Taylor said she met Pistorius in 2010, when she was 17, and they started dating the following year. She said they broke up twice, the second time on November 4, 2012, after he took Steenkamp to a sports banquet.

Roux asked if Taylor admitted in two e-mails to cheating on Pistorius. Taylor says she's never admitted to cheating on him but admits she had a relationship with another man after they broke up the first time.

Roux asked Taylor for details about the time he supposedly shot the gun out of the sunroof, but Taylor could not remember the name of the highway or the location in South Africa. She testified that Pistorius was angry and irritated after the traffic stop, even though he was not driving. She said he joked around about firing a shot and then laughed after he fired.

Finding inconsistencies

Nel put four neighbors of Pistorius on the stand in the first week of the trial, all of whom described hearing screaming and loud bangs they thought were gunshots the night of the killing.

Roux then tried to find inconsistencies or uncertainty in their stories. The defense goal is to prove there is a reasonable doubt about the guilt of the accused.

One of the most dramatic witnesses was a neighbor, Johan Stipp, who rushed to the track star's home the night he shot Steenkamp.

Pistorius broke down in court as Stipp said he saw Steenkamp lying on the floor, her brain tissue mixed with blood and Pistorius praying for her to live.

"I remember the first thing he said when I got there was, 'I shot her, I thought she was a burglar and I shot her,' " Stipp told the court in Pretoria.

Although Stipp is a prosecution witness, his testimony may bolster the defense case, CNN legal analyst Kelly Phelps said after Thursday's gripping testimony.

Prosecutors appear to have been trying to demonstrate that Pistorius and Steenkamp had a loud argument before the shooting, suggesting it's the reason he killed her.

But the defense is proposing that what neighbors thought was Steenkamp screaming in fear for her life was in fact Pistorius when he realized what he had done.

Pistorius and at least two neighbors made phone calls to security after the shooting, allowing the defense to use phone records to establish a timeline of events.

Stipp's version of events appears to coincide with the defense case, said Phelps, who teaches law at the University of Cape Town.

Trial may last three weeks

Judge Masipa will decide whether Pistorius is innocent or guilty. South Africa does not have jury trials.

In South Africa, premeditated murder carries a mandatory life sentence, with a minimum of 25 years. Pistorius also could get five years for each gun indictment and 15 years for the firearms charge.

If he isn't convicted of premeditated murder, the sprinter could face a lesser charge of culpable homicide, a crime based on negligence, and could be looking at up to 15 years on that charge, experts said. The trial is expected to take at least three weeks.

Pistorius and Steenkamp were a young, attractive, high-profile couple popular in South Africa's social circles.

Pistorius, whose "Blade Runner" nickname reflects the special prostheses he uses while running, won six Paralympic gold medals and became the first double-amputee runner to compete in the Olympics, in London in 2012.

Steenkamp, a model who was soon to star in a TV reality show, was on the cusp of becoming a celebrity in her own right at the time of her death.