Watch: Oscar Pistorius apologises to Reeva Steenkamp's family and friends

A tearful, stuttering and seemingly grief-stricken Oscar Pistorius began his testimony on Monday by apologising to the Steenkamp family

“I will start my evidence by tendering an apology,” he said. “I would like to apologise to Mr and Mrs Steenkamp, her family and friends.”

“I can’t imagine the pain and the sorrow and the emptiness I have caused you and your family.

“You're the first people I think of when I wake up. You're the first people I pray for. I was trying to protect Reeva. When she went to bed that night, she felt loved.

“I’ve tried to put my pen to paper many times to write to you but no words would ever suffice.”

Pistorius also revealed that he has been taking anti-depressants since the accident happened, and other medication to help him sleep at night.

"I'm scared to sleep,” he said tearfully. “I have terrible nightmares about what happened that night. I can smell blood. I wake up terrified."