Pretoria, South Africa (SportsNetwork.com) - South African sprinter Oscar Pistorius began testifying in his own defense at his murder trial on Monday.
Pistorius, the double-amputee runner, shot and killed his girlfriend, Reeva Steenkamp, on Feb. 14, 2013 in the bathroom of his home. He has said he thought Steenkamp was an intruder and mistakenly killed her. Prosecutors have countered that Pistorius knew Steenkamp was in the bathroom when he fired the four shots through the door.
The trial began on March 3 and had been delayed for more than a week because of a judge's aide's illness after the prosecution rested its case on March 25.
Pistorius was emotional during his testimony on Monday, saying not a day goes by that he doesn't think about Steenkamp, her family and the events of the shooting.
"I would like to take this opportunity to apologize to Mrs. and Mr. Steenkamp," said Pistorius as he looked toward Steenkamp's family in court. "There hasn't been a moment since this tragedy happened that I haven't thought about your family. I wake up every morning and you are the first people I think of, the first people I pray for. I can't imagine the pain and the sorrow and the emptiness that I have caused your family. I was simply trying to protect Reeva."
The trial is being broadcast throughout South Africa and other parts of the world.
Pistorius is not being shown as he testifies. Only the audio portion of his statements are audible as the cameras take shots of the judge, attorneys and court room.
Judge Thokozile Masipa will decide guilt or innocence in the case, as South Africa does not have trial by jury.
In addition to the murder charge, Pistorius also faces charges of contravening South Africa's Firearms Control Act.
The murder charge could carry a sentence of life in prison. There is no death penalty in South Africa.
Pistorius added that he has had trouble sleeping and is on medication. He said he sometimes wakes up terrified because of the incident.
"I'm just in a complete state of terror," Pistorius said. "I fall asleep and wake up like that."
In an affidavit during his bail hearing last year, Pistorius said he heard a noise in the bathroom and, thinking it was an intruder, got his gun -- a 9-mm pistol he said he keeps under his bed for protection. He said he fired shots through the door and told Steenkamp to call the police.
When he realized Steenkamp was not in bed with him, Pistorius thought it may have been her in the bathroom. He said he called paramedics and security officers in his building complex, and tried to carry her down the stairs for help. He said she died in his arms.
Steenkamp, who was 29 years old, was a model and reality television star in South Africa.
Pistorius, known as the "Blade Runner," made history at the London Olympics in 2012 when he became the first double-amputee runner to compete in the Games. He had both legs amputated before he was a year old after being born without fibula bones and runs on prosthetic blades.
The International Association of Athletics Federations (IAAF) had initially said that his prosthetics were considered technical aids and in violation of an IAAF rule. But the Court of Arbitration for Sport later overturned that decision, making him eligible to compete against able-bodied runners.
Pistorius qualified for South Africa's Olympic team in 2012 and competed in the 400-meter race, reaching the semifinals, and the 1,600-meter relay.
04/07 08:25:21 ET